CP Chemistry
Laboratory Activities
2010-2011
Theodore Roosevelt High School
Mr. Carman & Mr. Knopick
Lab Activities Syllabus
The order and content of this syllabus may change depending on school events, snow days, materials
availability, and other schedule disruptions.
Q1: The Nature of Chemistry
Target(s)
I. Nature of Science
#1-0: Using Logic to Explain (Stations)*
SM
II. Matter & Energy
#1-1: Alchemy
#1-2: Physical vs. Chemical Changes
#1-3: Law of Definite Proportions
#1-4: Flame Test
HPS, CM
PCC
CM, HMA
PT, EGF
III. Chemical Equations
#1-5: Types of Chemical Reactions
#1-6: Reactivity of Metals
Q1 Capstone Lab
#1-7: Activity Series of Metals Using Fruit
Q2: Chemical Quantities
CR, WE, IPR
CR, WE, IPR
Target(s)
I. Scientific Measurement
#2-0: Scientific Measurement (Stations)*
#2-1: SI Scavenger Hunt
#2-2: Density Blocks
SI
SI
SI, DPM
II. Chemical Quantities
#2-3: Atomic Mass of “Beanium”
#2-4: Composition of a Penny
MSA
PC
III. Stoichiometry
#2-5: Stoichiometry
#2-6: Limiting Reagents: Turning Iron into Copper
Q2 Capstone Lab
#2-7: Bulbous Balloon Challenge
* Stations labs will not require a write-up to be submitted.
MMC, PY
MMC, LR
Q3: Kinetic Theory
Target(s)
I. States of Matter
#3-1: Change of Physical State
CS
II. Thermochemistry
#3-2: Calorimetry
#3-3: Heat of Combustion of a Candle
HCC, CHC
CHC
III. The Behavior of Gases
#3-0: Gas Laws (Stations)*
#3-4: Molar Mass of Butane
#3-5: Ideal Gas Constant
PG, IGL
MM, PG
IGL
IV. Nuclear Chemistry
#3-6: Half-Life of a Penny
Q3 Capstone Lab
#3-7: Measuring the Energy Content of Food
Q4: Chemistry & Society
HLC
Target(s)
I. Water, Aqueous Systems & Solutions
#4-0: Properties of Water (Stations)*
#4-1: Dilution of Solutions
#4-2: Supersaturation
WAS, PS
PS, CoSD
PS, CoSM
II. Acids & Bases
#4-3: Natural Indicators
#4-4: Acid-Base Titration
#4-5: Testing Antacids
PAB, CPH
ABR, NR
ABR, NR
III. Organic Chemistry
#4-6: Making Artificial Fragrances
Q4 Capstone Lab
#4-7: Purification of Water
* Stations labs will not require a write-up to be submitted.
HC, OFGP
Laboratory Know-How
In order to be successful in the chemistry laboratory, it’s important to follow proper procedures, or “best
practice”, at all times. This is necessary not just to get good results, but also to be safe and to work
efficiently!
I.
KNOW WHAT YOU’RE DOING
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II.
Read all directions before you start to work
When in doubt, ask your teacher to explain
Use only the materials and amounts listed in the experiment procedure
Make substitutions only when told to do so by your teacher
PROPERLY OBSERVE ALL LABORATORY SAFETY PROCEDURES
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Always wear safety goggles while working in the laboratory
Wear a lab apron when working with corrosive chemicals
Fasten long hair back
Never taste, eat or drink anything in the laboratory
Immediately wash off any chemical that comes in contact with your eyes or skin; wash eyes
at the eye wash station for at least 15 minutes; flood skin with running water for at least 2
minutes
If your skin itches or burns, flood it with water; tell your teacher if the itching or burning
persists
Keep your face away from containers being heated, and don’t lean over your work area
Wear close-toed shoes (no sandals!)
Avoid inhaling toxic fumes by using the fume hood
Wash your hands before leaving the lab
Report all accidents to your teacher immediately!
III. PREVENT ACCIDENTS FROM OCCURRING
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Work in a businesslike manner
Avoid moving about in the lab
Clean up spilled chemicals by first flooding them with water and then wiping them up with
paper towels or a sponge
Keep your lab drawer closed unless you are removing or putting away equipment
Don’t reach over a lit burner
Turn off a burner as soon as you are finished heating something
Avoid touching iron rings and wire gauze after they’ve been heated – they stay hot for quite
a while
Heat only PYREX glassware; never use glassware that has been chipped and cracked
Put broken glassware in the proper container, NOT the trash
Put used chemicals in the proper container as designated by your teacher
Know where the nearest fire extinguisher, fire alarm, emergency shower, eye wash station
and fire blanket are located and know how to use them
IV. AVOID CONTAMINATION OF CHEMICALS
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Never return any excess chemical to its original container (stock bottle); discard the extra
chemical as you would discard used chemicals
Never lay the stoppers or corks of a reagent bottle down on the lab bench or supply table;
hold stoppers between your fingers and set corks down upside-down so they do not become
contaminated or inadvertently drip any chemicals
Replace stoppers and corks immediately after removing a chemical from its bottle, as the
chemical may be affected by the air or moisture
Use only clean, dry spoons or spatulas to remove solids from their containers
Take care not to mix up spoons or spatulas when multiple solids are being used
Rinse and dry stirring rods before using them to stir other liquids
Be sure all glassware is clean before using; drops of water will not cling to clean surfaces
V. STUDY OBSERVATIONS BEFORE ANSWERING QUESTIONS
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Look for differences as well as similarities – patterns are key!
Think about what the question means before answering it.
Look up any terms you do not understand in your textbook or on the Internet.
Record any other questions or thoughts you may have that might lead to future experiments
or discussion.
VI. TAKE APPROPRIATE PRECAUTIONS BASED ON SAFETY SYMBOLS
Laboratory Safety Rules
“I agree to comply with the following laboratory procedures to help ensure my safety and the
safety of others in the laboratory:”
1.
I will wear safety goggles at all times while working in the lab. If I wear contact lenses, I
will consult with my eye care professional about wearing contact lenses in the lab.
2.
I will wear a lab apron whenever chemicals are being used.
3.
I will confine long hair and loose clothing or jewelry.
4.
I will wear close-toed shoes in the lab (no sandals!).
5.
I will perform only assigned experiments and procedures.
6.
I will follow closely all written and verbal instructions. I will read the lab procedures before
the lab, and I will not skip steps.
7.
I will read chemical labels twice before using any reagent.
8.
I will put NOTHING in my mouth while working in the lab.
9.
I will not eat or drink ANYTHING in the classroom.
10. I will use the “wafting” method when noting odors. I will use the fume hood when working
with chemicals that have noxious or toxic fumes.
11. I will keep flames away from any substance or object not involved in the lab. I will keep
flames away from flammable liquids.
12. I will heat only PYREX glassware that is free of chips and cracks.
13. I will dispose of broken glass ONLY in the “Broken Glassware” box; I will NOT place any
other trash in the “Broken Glassware” box.
14. I will distribute heat evenly along test tubes while pointing the open mouth away from
anyone nearby.
15. I will report any injuries immediately to the teacher.
16. I will NOT put solids in the sink under any condition.
17. I will clean my lab area and glassware, return materials to their proper places, dispose of
any chemicals in their proper location, place trash in the trash can, and wash my hands
before leaving the lab.
How to Write a Lab Report
"An experiment is only as good as the lab report that describes it."
Lab reports are an essential part of all college laboratory courses and usually a significant part of your
grade. A lab report is how you explain what you did in experiment, what you learned, and what the
results meant. In CP Chemistry, you will submit your lab reports via Moodle, available at
http://www.kentschools.net/moodle/, within two days of completing the lab activity in class. Lab
reports will account for 30% of your total quarter grade.
Every lab report should have each of the following:
Header and Title (2 pts)
At the top of each lab report, you must list the following information:
• Your name and the names of any lab partners
• Your teacher’s name
• The date and time the lab was performed
• The title of the experiment.
Purpose (1 pt, as needed)
Normally, a scientist would write several paragraphs or even pages explaining why they are putting
forth the effort to
Data / Observations / Calculations (varies)
Numerical data obtained from your procedure usually is presented as a table. Data encompasses what
you recorded when you conducted the experiment. This sections should just include the facts, not any
interpretation of what they mean.
Questions (6 pts)
This is where you will perform any calculations and answer any questions based on your data and/or
observations. Calculations worth more than one point usually require more than one step; questions
worth more than one point usually require more than one answer.
Errors (4 pts)
This is where you discuss any mistakes (at least two) you might have made while conducting the
experiment and describe the ways you might avoid those errors in future experiments. Stating our
Conclusion (5 pts)
Your conclusion should consist of at least two paragraphs that sum up what happened in the
experiment, whether your hypothesis (prediction) was accepted or rejected, and what your data and
results mean. Your interpretation of the experiment and its results is the most important part of your lab
report!
Modified from “How to Write a Lab Report: Lab Reports Describe Your Experiment” by Anne Marie Helmenstine, Ph.D.,
About.com (http://chemistry.about.com/od/chemistrylabexperiments/a/labreports.htm)
st
1 Quarter
Laboratory Activities
CP Chemistry
Theodore Roosevelt High School
Lab #1-0
Stations Lab: Using Logic in Science
Introduction
Each scientist has to use some form of logic to explain his or her
observations of the natural world. However, deciding what type of logic to
use can be as challenging as coming up with the explanations themselves.
Induction allows the scientist to take many specific observations and
develop a general theory. Deduction allows scientists to start with a
“hunch” or possible explanation, and then search for specific examples
that support that explanation. Finally, abduction combines the previous
two methods, using the same basic structure as induction but allowing for
scientists to use their prior experience to apply the best known conclusion.
By observing several scientific phenomena in this lab, you will discover that each logical method has its
own advantages and disadvantages. Because this is an exploratory stations lab, you will not be
required to turn in a write-up on Moodle for this activity.
Purpose
To practice explaining observations of scientific phenomena.
Equipment & Materials
varies
Safety Considerations
• Stations 4 & 5 use acids and bases that require you to wear goggles for safety.
• Stations 5 & 7 use dry ice, which can cause frostbite with prolonged exposure to the skin. Only
use tongs to manipulate the dry ice, NOT your hands.
Procedure
1.
Complete the activities at each of the eight lab stations per the supplied directions.
2.
Record your observations for each lab station.
CP Chemistry
Theodore Roosevelt High School
Lab #1-0
Data – record your data in the table below:
Station
Observations
Station 1
Station 2
Station 3
Station 4
Station 5
Station 6
Station 7
Station 8
Questions for discussion
1.
Did you follow the scientific method while completing this lab? If so, give an example. If not,
explain why not.
2.
Scientists often have to rely on imagination in their field to achieve results. Does this match with
what you experienced in today’s lab? Why or why not?
3.
How did you come up with your explanations for what you observed at the stations? Did you use
induction, deduction, abduction, or a combination of the three?
Errors
Think of two possible errors you may have committed in this lab that may have somehow affected your
results and record them below. Explain the specific steps you will take to avoid each of these errors in
the future.
1.
2.
Conclusion
Describe what you learned while doing this lab:
CP Chemistry
Theodore Roosevelt High School
Lab #1-1
Alchemy Lab
Introduction
Alchemy was a mixture of science, medicine, magic and religion. Many of the
processes and substances that we know today were discovered by
alchemists. They discovered alcohol, hydrogen, phosphorus and gun powder,
as well as the processes of distillation, evaporation and filtration. However,
one of the main goals of alchemy was to change a lesser metal such as
copper into gold. Producing gold was thought by the alchemists to be a major
step toward everlasting life.
Imagine that you’re back in the Middle Ages when alchemists were at work trying to perfect their
methods of producing gold. The King has just asked for your advice in the case of a local alchemist,
who claims to have devised a way to make copper into silver and then into gold. Your instructions are
to reproduce the experiment, test the gold, and give the King your advice – should he reward the
alchemist or hang him as a cheat? The King is very gracious in his rewards for good work and harsh in
his punishments for wrong answers.
Purpose
To use the Law of Conservation of Mass to test whether or not a copper penny can be turned into gold.
Prediction
Do you think you will actually be able to turn a penny into gold? Why or why not?
Equipment
balance
beaker (100 mL)
beaker (250 mL)
Bunsen burner
iron rings
ring stand
Materials
copper tokens (pennies)
sodium hydroxide [3M NaOH (aq)]
ruler
scoopula
stirring rod
striker
tongs
wire gauze
zinc powder
Safety Considerations
• Sodium hydroxide (NaOH) in this concentration is caustic and can be damaging to the eyes,
skin and respiratory system. Wash your skin with soap immediately if you come into contact
with NaOH. Avoid breathing the fumes from the boiling NaOH.
• Zinc powder can spontaneously combust as it dries. Make sure you leave no clumps of zinc on
paper towels, and place all excess zinc in the waste beaker provided by your teacher.
• Be sure you wear your goggles for the entire lab.
• Always report spills and splashes to your teacher.
CP Chemistry
Theodore Roosevelt High School
Lab #1-1
Procedure
1.
Set up a ring stand with wire gauze and two iron rings. Place the wire gauze on the bottom ring
and arrange the top ring so it will surround the 250mL beaker.
2.
Pour approximately 100 mL of 3M sodium hydroxide (NaOH) solution into a 250mL beaker and
heat until it water vapor begins to come off.
3.
Pour approximately 50mL of tap water in a 100mL beaker and set aside. This will be the wash
beaker.
4.
Measure the mass of a clean copper token. Record this mass.
5.
Measure the thickness and diameter of the clean copper token. Record these data.
6.
Using tongs, immerse a clean copper token in the hot NaOH solution. Place a “pinch” of zinc
powder in the solution. Continue stirring the token until a color change has occurred. Move the
Bunsen burner away from the beaker, but do not turn it off.
7.
Remove the token from the NaOH solution and place it in the wash beaker. Scrape off any
excess zinc on the tokens and dry it with a paper towel. Measure and record the mass of the
token.
8.
Using tongs, gently hold the token by its edges and heat it in the Bunsen burner flame for a few
seconds until a complete color change occurs. Quickly place the token in the water to cool.
9.
After the token cools, remove it from the wash beaker and dry it. Measure and record its mass.
10. If time allows, you may repeat the experiment with your own copper tokens.
Additional Clean-up and Disposal
1.
Dispose of any remaining NaOH solution and zinc powder in the waste beaker provided by your
teacher. DO NOT POUR EXCESS SOLUTION OR ZINC POWDER DOWN THE SINK.
Data – you should create a data table in your lab write-up that looks something like this:
Token color
Mass
Thickness
Diameter
Volume*
Density*
copper token
silver token
Calculations (Include these answers in your Data Table!)
1.
Using the equations Vcylinder = πr2t and r = ½ d, and the thickness and diameter you recorded in
Procedure #5, calculate the volume of the token.
2.
Using the equation m = D x V, calculate the theoertical mass of the token at each stage (copper,
silver and gold) by using the given densities of those metals and the volume of the token
(DCu = 9.0 g/cm3, DAg = 10.5 g/cm3, DAu = 19.3 g/cm3).
Questions
1.
Was the change in the tokens a physical change or a chemical change? Give evidence for your
claim.
2.
Based on your data, calculations and observations, is the gold token really gold? Give evidence
for your claim.
3.
Pennies made before 1982 are solid copper; after 1982, they are made mostly of zinc with a thin
copper outer coating. Do you think your results would be affected by which kind of penny you
use? Why or why not?
CP Chemistry
Theodore Roosevelt High School
Lab #1-1
Errors
Describe two possible errors you may have committed in this lab that may have somehow affected your
results. Explain the specific steps you will take to avoid each of these errors in the future.
Conclusion
Write two or more paragraphs summarizing your results, examining the validity of your prediction, and
explaining your calculations.
CP Chemistry
Theodore Roosevelt High School
Alchemy Lab workspace:
Lab #1-1
CP Chemistry
Theodore Roosevelt High School
Lab #1-2
Physical & Chemical Changes Lab
Introduction
In Chemistry, you should always be watching for changes when you perform lab
experiments. Some changes will be obvious, like dramatic color changes and changes
of state. Some will be almost undetectable, like the slow reaction between oxygen and
iron to form rust. Sometimes there will be no change at all, but this observation of “no
change” is just as important as observations of change.
It is important that the observations you make and record in the lab be as specific and
informative as possible. For example, you may observe a gas being given off as a result of a chemical
reaction. You should write your observation as “gas formed” rather than “it fizzed”. Whenever possible,
try to quantify the changes you observe using numbers or comparative terms like “large” or “small”. If
you think the mass has changed, use a balance to determine how much the mass has changed. If you
observe the “material became hotter”, use a thermometer to determine how much the temperature
changed.
Purpose
To observe chemical and physical changes; to explain observations of changes accurately and
completely; to recognize patterns of observations.
Prediction
Do you think we will perform more physical changes or chemical changes in this lab? Why do you think
so?
Equipment
scoopula
small test tubes
stirring rod
Materials
ammonium chloride [NH4Cl (s)]
calcium carbonate [CaCO3 (s)]
calcium chloride [CaCl2 (s)]
sodium bicarbonate [NaHCO3 (s)]
starch (s)
sucrose [C12H22O11 (s)]
test tube rack
well plate
acetic acid [1M HC2H3O2 (aq)]
iodine solution (aq)
phenolphthalein indicator (aq)
potassium iodate [0.1M KI2O4 (aq)]
sodium bisulfite [0.05M NaHSO3 (aq)]
sodium hydroxide [0.05M NaOH (aq)]
sodium sulfate [1M Na2SO4 (aq)]
strontium chloride [1M SrCl2 (aq)]
Safety Considerations
• Iodine solution is corrosive to skin and eyes. Immediately wash spills and splashes off your skin
and clothing using plenty of water.
• Acetic acid and sodium hydroxide in these concentrations can also be damaging to the eyes.
• Be sure you wear your goggles and lab apron for the entire lab.
• Always report spills and splashes to your teacher.
CP Chemistry
Theodore Roosevelt High School
Lab #1-2
Procedure
1.
Using the small test tubes, mix the following chemicals; use a pea-sized sample of each solid and
½ a test tube for each liquid or solution. Hold the test tubes over the sink when adding liquids.
Stir each mixture with a stirring rod. Be sure to rinse the stirring rod after each use. Record your
observations, quantifying them when possible.
a.
ammonium chloride + distilled water
b.
calcium chloride + distilled water
c.
sodium bicarbonate + acetic acid solution
d.
calcium carbonate + acetic acid solution
e.
sucrose + distilled water
2.
Using a well plate, mix the following chemicals in the amounts listed. Stir each mixture with a
stirring rod. Be sure to rinse the stirring rod after each use. Record your observations,
quantifying them when possible.
a.
5 drops sodium hydroxide solution + 1 drop phenolphthalein solution
b.
5 drops acetic acid solution + 1 drop phenolphthalein solution
c.
5 drops sodium bisulfite solution + 5 drops potassium iodate solution
d.
a pea-sized sample of starch + 10 drops distilled water + 1 drop iodine solution
e.
5 drops strontium chloride solution + 5 drops sodium sulfate solution
Data – you should create a data table in your lab write-up that looks something like this:
Chemicals
Observations
1a. NH4Cl + H2O
1b. CaCl2 + H2O
Questions
1.
List each procedure step that represented a physical change and give evidence for why each was
a physical change.
2.
List each procedure step that represented a chemical change and give evidence for why each
was a chemical change.
3.
What was the most common evidence of a chemical change that you encountered in the lab?
What chemicals produced this evidence?
Errors
Describe two possible errors you may have committed in this lab that may have somehow affected your
results. Explain the specific steps you will take to avoid these errors in the future.
Conclusion
Write two or more paragraphs summarizing your results, examining the validity of your prediction, and
explaining the difference between physical and chemical changes.
CP Chemistry
Theodore Roosevelt High School
Physical & Chemical Changes Lab workspace:
Lab #1-2
CP Chemistry
Theodore Roosevelt High School
Lab #1-3
Law of Definite Proportions Lab
Introduction
Elements are a kind of matter that can’t be broken down by ordinary chemical
means. Compounds are chemical combinations of elements that have their
own properties that are distinct from the properties of their elements.
According to the law of definite proportions, elements forming a compound
always combine in the same proportion by mass. We can use this information
to identify unknown substances as well as to predict how much of each
reactant will be needed in order to perform a chemical reaction.
In this lab, you will examine the reaction between magnesium metal (Mg) and
oxygen gas (O2). When heated strongly in an open crucible, magnesium reacts readily with oxygen in
the air. You will measure the mass of the magnesium that reacts as well as the mass of magnesium
oxide that is formed. This will allow you to calculate the mass of oxygen that reacted as well as the
mass ratio between magnesium and oxygen. Finally, you will compare your experimental mass ratio to
the accepted value to determine how successful your experiment was!
Purpose
To observe a chemical reaction between magnesium and oxygen; to calculate a mass ratio of
magnesium to oxygen; to practice measuring carefully in order to obtain accurate results.
Prediction
How close do you think your results will be to the accepted ratio of magnesium to oxygen (1.52 : 1)?
Why do you think so?
Equipment
balance
Bunsen burner
clay triangle
crucible w/lid
crucible tongs
iron ring
Materials
distilled water
ring stand
scissors or tin snips
sandpaper or steel wool
striker
wash bottle
magnesium [Mg (s)]
Safety Considerations
• The crucible will get very hot during this experiment and may appear to be cool even when it is
not. Do not handle the crucible with your bare hands; only move it using the crucible tongs.
• Safety goggles must be worn at all times.
• Sometimes chemicals from previous labs still remain in glassware and on other lab equipment.
Wash all lab equipment before and after performing this lab.
Procedure
1.
Obtain a piece of magnesium ribbon that is approximately 20 cm long. If the surface of the
magnesium is not shiny, use a piece of sandpaper or steel wool to shine the surface.
2.
Measure the mass of your dry, clean crucible and its lid; record this value.
CP Chemistry
3.
4.
5.
6.
7.
8.
9.
Theodore Roosevelt High School
Lab #1-3
Roll the magnesium ribbon into a loose coil and place it at the bottom of the crucible. Measure
the total mass of the crucible, lid and magnesium; record this value.
Set up the ring stand with an iron ring and clay triangle so that the crucible can sit in the triangle
approximately two inches above the Bunsen burner per the diagram above. Place the crucible in
the clay triangle and make sure its lid is completely on.
Using the Bunsen burner, heat the crucible gently by slowly moving the flame around underneath
it. If a large amount of smoke appears from the crucible, remove the heat temporarily until it stops
smoking.
After about four minutes of direct heating without any smoke produced, use the crucible tongs to
remove the lid slightly. Heat the crucible to redness for four minutes. Finally, remove the lid
completely and heat strongly for four more minutes.
Turn off the Bunsen burner and put the lid back on the crucible, allowing them to cool enough so
that they are safe to touch (be careful not to burn yourself!). Determine the total mass of the
crucible, lid and magnesium oxide product; record this value.
Add ten drops of distilled water to the crucible, replace the lid, and heat it for an additional four
minutes.
Repeat Procedure step #7. If there is a difference of more than 0.03 g between this measurement
and the last, you must repeat this step until there is an agreement between these values. Make
sure you record the mass each time!
Additional Clean-up and Disposal
1.
Dispose of the magnesium oxide product in the trash.
Calculations (Include these answers in your Conclusion!)
1.
Calculate the mass of magnesium that reacted by subtracting the mass of the crucible and lid
from the mass of the crucible, lid and magnesium.
2.
Calculate the mass of magnesium oxide that was produced by subtracting the mass of the
crucible and lid from the mass of the crucible, lid and magnesium oxide.
3.
Calculate the mass of oxygen that was reacted by subtracting the mass of magnesium from the
mass of magnesium oxide.
4.
Find the mass ratio of magnesium to oxygen by dividing the mass of magnesium by the mass of
oxygen.
Data – you should create a data table in your lab write-up that looks something like this:
Object
Mass
crucible & lid
crucible, lid & Mg
Questions
1.
The accepted mass ratio of magnesium to oxygen in magnesium oxide is 1.52 g : 1.00 g. How
close was your final result to the accepted value? Why do you think this happened?
2.
How would your results be affected if all the magnesium did not react?
3.
Determine the correct formula for magnesium oxide. How does the mass ratio of magnesium and
oxygen compare to the ratio of elements in the chemical formula? Why do you think this is?
CP Chemistry
Theodore Roosevelt High School
Lab #1-3
Errors
Describe two possible errors you may have committed in this lab that may have somehow affected your
results. Explain the specific steps you will take to avoid each of these errors in the future.
Conclusion
Write two or more paragraphs summarizing your results, examining the validity of your prediction, and
explaining your calculations.
CP Chemistry
Theodore Roosevelt High School
Law of Definite Proportions Lab workspace:
Lab #1-3
CP Chemistry
Theodore Roosevelt High School
Lab #1-4
Flame Test Lab
Introduction
When an atom is heated, electrons absorb energy in definite amounts, and as they
cool, they emit that extra energy which we see as a particular color of light. When
heated, each element emits a characteristic pattern of light energies that is useful
for identifying that element. This pattern is caused by the electrons “jumping” down
to set, lower energy levels and emitting photons of specific colors (and therefore
energies) of light. In this lab, you will determine the flame colors generated by
several nitrate salts, and then attempt to identify two chloride salts by heating them in the flame.
Purpose
To observe the colors emitted by various metal ions; to identify unknown salts by the color of their
flames.
Prediction
Do you think it will be easy or difficult to identify the unknown salts? Why?
Equipment
beakers (250-mL and 400-mL)
Bunsen burner
Materials
barium nitrate [Ba(NO3)2 (s)]
calcium nitrate [Ca(NO3)2 (s)]
copper (II) nitrate [Cu(NO3)2 (s)]
iron (III) nitrate [Fe(NO3)3 (s)]
lithium nitrate [LiNO3 (s)]
potassium nitrate [KNO3 (s)]
sodium nitrate [NaNO3 (s)]
strontium nitrate [Sr(NO3)2 (s)]
unknown salts (“A” and “B”)
wooden splints
Safety Considerations
• Wooden splints must be soaked in a ‘waste beaker’ after being used, otherwise they can set
trash can contents on fire.
• Avoid inhaling any fumes given off by the burning salts.
• Be sure you wear your goggles for the entire lab. You may also want to wear a lab apron.
• Always report spills and splashes to your teacher.
• Some of the salts are toxic; be sure to wash your hands after you’ve completed the experiment
and before you leave the lab.
Procedure
1.
Fill a 250-mL beaker halfway full of tap water to use as a
soaking beaker for the wooden splints.
2.
Fill a 400-mL beaker halfway full of tap water to use as a
waste beaker.
3.
Light the Bunsen burner.
4.
Obtain one sample of salt from the supplies table.
5.
Test a small portion of the salt sample in the flame by using a
pre-soaked wooden splint. Be careful not to let any of the salt
fall into the Bunsen burner. Do not allow the splint to burn, as this will affect your results. Record
the color of flame generated by the salt.
CP Chemistry
6.
7.
8.
Theodore Roosevelt High School
Lab #1-4
Place the used wooden splint in your waste beaker.
Repeat Steps #4-6 for each salt sample, using a new wooden splint and recording your results for
each.
Obtain one of the unknown samples (“A” or “B”) from your teacher and test it using the same
procedure described above. Record the color of the flame generated by the salt and
determine its metal ion by comparing it to your known samples from above. Repeat the
same procedure for the other unknown sample.
Additional Clean-up and Disposal
1.
Wet any used wooden splints and throw them away in the trash can. DO NOT LEAVE ANY
SPLINTS IN THE SINK OR AT YOUR LAB STATION.
Data – you should create a data table in your lab write-up that looks something like this:
Metal Ion
Flame Color
barium
calcium
Questions
1.
Do you think that flame tests would be a valid means of detecting metal ions present in a mixture
of ions? Why or why not?
2.
The energy of visible light increases from the least energetic color, red, to the most energetic
color, violet. List the ions used the flame tests in increasing order of the energy of their emitted
light.
3.
What conclusion can you make about the relationship between metal ions and the emission of
light?
Errors
Describe two possible errors you may have committed in this lab that may have somehow affected your
results. Explain the specific steps you will take to avoid each of these errors in the future.
Conclusion
Write two or more paragraphs summarizing your results, examining the validity of your prediction, and
identifying the unknown metal ions.
CP Chemistry
Theodore Roosevelt High School
Flame Test Lab workspace:
Lab #1-4
CP Chemistry
Theodore Roosevelt High School
Lab #1-5
Types of Chemical Reactions Lab
Introduction
During any chemical reaction, the Law of Conservation of Matter must be satisfied,
meaning that there must be the same kind and number of atoms on each side of the
chemical equation. Recognizing and using categories of reactions can make determining
the reactants and products much easier. The five general types of reactions that you will
study in this lab activity are: combination, decomposition, combustion (or burning), single
replacement (or displacement), and double replacement (or ionic).
Purpose
To observe chemical reactions in order to determine their types; to practice writing chemical equations.
Prediction
Based on the directions, which reaction do you think will be the most interesting? Why do you think so?
Equipment
beaker (600 mL)
Bunsen burner
forceps
small test tubes
stirring rod
striker
test tube holders
tongs
wash bottle
watch glass
well plate
Materials
aluminum foil
candle
pH paper
wooden splints
calcium [Ca (s)]
calcium oxide [CaO (s)]
copper (II) carbonate, basic [CuCO3 · Cu(OH)2 (s)]
copper (II) sulfate, pentahydrate [CuSO4 · 5H2O (s)]
copper (II) sulfate solution [CuSO4 (aq)]
lead (II) nitrate solution [Pb(NO3)2 (aq)]
magnesium ribbon [Mg (s)]
potassium iodide solution [KI (aq)]
silver nitrate solution [AgNO3 (aq)]
sodium chloride solution [NaCl (aq)]
zinc [Zn (s)]
Safety Considerations
• Several of the chemicals in this lab are slightly to moderately toxic. YOU MUST WEAR
GOGGLES AT ALL TIMES.
• The silver and lead-based chemicals are toxic; DO NOT POUR THEM DOWN THE SINK.
Instead, pour them in the specially marked waste containers.
• DO NOT look directly at the magnesium ribbon while burning.
• When heating test tubes, keep them slightly tilted and pointed away from yourself and other
students; DO NOT LOOK DOWN INTO THE TEST TUBE.
CP Chemistry
Theodore Roosevelt High School
Lab #1-5
Procedure
Part A – Single Replacement Reactions
1.
Obtain a clean well plate.
a. Place a small piece of zinc metal in one well. Record your observations.
b. Fill the well about two-thirds full of copper (II) sulfate solution.
c. Observe the zinc and solution. Return to this station later to observe any changes and
record your observations.
2.
Repeat step 1, but instead use a small piece of calcium and distilled water in another well plate.
Part B – Combination Reactions
1.
Obtain a small piece of magnesium ribbon. Record your observations of the metal.
a. Light and adjust the Bunsen burner to a hot blue flame.
b. Using tongs, hold one end of the magnesium in the hot outer cone of the flame. Once the
magnesium ribbon has ignited, hold it over your lab station. CAUTION: DO NOT LOOK
DIRECTLY AT THE BURNING MAGNESIUM.
c. Observe the properties of the product. Record your observations.
2.
Place a tiny lump of calcium oxide (about the size of a match head) in a clean well of the well
plate. Observe and record your observations.
a. Fill the well about two-thirds full with distilled water.
b. Use the stirring rod to mix the calcium oxide and water. Record your observations.
c. Place ½ strip of red and ½ strip of blue litmus paper on your lab station.
d. Using the stirring rod, place a drop of the solution from the well on each litmus strip. Record
your observations.
Part C – Decomposition Reactions
1. Place a small crystal of copper (II) sulfate, pentahydrate in a small, dry test tube. Record your
observations.
a. Hold the test tube over the lab station with the mouth of the test tube tilted slightly
downwards. Evenly heat the bottom portion of the test tube with a hot flame. Record your
observations of the materials being given off from the test tube.
b. Allow the test tube to cool in a rack. You may want to complete other stations and then
return later.
c. After the test tube has cooled completely, add a few drops of water to the contents of the test
tube. Note the temperature of the bottom of the test tube. Record your observations.
2. Place a small amount of copper (II) carbonate, basic (about the size of a small pea) in a dry test
tube. Record your observations.
a. Using a test tube holder, evenly heat the test tube with a hot flame, making observations
throughout the procedure.
b. When the reaction is complete, allow the material to cool. Record your observations.
Part D – Double Replacement Reactions
1. Place a few drops of potassium iodide solution in a clean well. Record your observations.
a. Add a few drops of lead (II) nitrate. Record your observations.
2. Repeat step 1, but instead use silver nitrate solution and sodium chloride. CAUTION: silver nitrate
solution can stain skin and clothing.
Part E – Combustion
1. Place a candle upright on the center of a foil-covered watch glass.
a. Carefully lower a beaker over the lighted candle.
b. Observe and record until no more changes are evident.
c. Light a splint, carefully lift one edge of the beaker and insert the lighted end into the beaker
next to the candle. Record your observations.
CP Chemistry
Theodore Roosevelt High School
Lab #1-5
Data – you should create a data table in your lab write-up that looks something like this:
Experiment
Reactants
(before)
Reaction
(during)
Products
(after)
A1
single
replacement
A2
single
replacement
B1
combination
…etc. for all experiments.
Questions
1.
What evidence do you have that the color of copper (II) sulfate pentahydrate is related to the
presence of water in the crystal?
2.
Would you predict that the “ash” formed when magnesium burned would have a greater or lesser
mass than the original piece of magnesium metal? Why?
3.
What evidence do you have that the product of calcium oxide and water is basic rather than
neutral or acidic?
Errors
Describe two possible errors you may have committed in this lab that may have somehow affected your
results. Explain the specific steps you will take to avoid each of these errors in the future.
Conclusion
Write two or more paragraphs summarizing your results, examining the validity of your prediction, and
identifying the unknown metal ions.
CP Chemistry
Theodore Roosevelt High School
Types of Chemical Reactions Lab workspace:
Lab #1-5
CP Chemistry
Theodore Roosevelt High School
Lab #1-6
Reactivity of Metals Lab
Introduction
In nature, elements can occur either free (uncombined with other elements) or
chemically combined in a compound. The tendency of an element to combine with
other substances is called the reactivity of that element. The more reactive an
element is, the more likely it is to combine with other substances. In a singlereplacement reaction, one element takes the place of another element in a
compound. In general, more reactive elements replace less reactive elements. As
a result of the reaction, the less reactive element is freed from the compound.
In the reaction between zinc (Zn) and copper (II) sulfate (CuSO4), the more reactive zinc replaces
copper and combines with the sulfate ion. The less reactive copper is released from the compound and
becomes a free element. Likewise, when a metal is placed in hydrochloric acid (HCl), a single
replacement reaction can occur. If the metal is more reactive than the hydrogen in the acid, the metal
will replace the hydrogen, and bubbles of hydrogen gas (H2) will be produced. The more reactive a
metal is, the more vigorously it will react with hydrochloric acid.
In this lab, you will determine whether or not various metals undergo single-replacement reactions
when placed in hydrochloric acid. Based on your observations of these reactions, you will then rank the
metals by reactivity.
Purpose
To determine the reactivity series of common metals; to observe single replacement reactions.
Prediction
Which metal will be the most reactive? Why do you think so?
Equipment
graduated cylinder (10 mL)
marker
test tubes, 5 small
test-tube rack
Materials
aluminum [Al]
copper [Cu]
hydrochloric acid, 1M [HCl]
iron [Fe]
magnesium [Mg]
zinc [Zn]
Safety Considerations
• Hydrochloric acid is damaging to the eyes; YOU MUST WEAR GOGGLES AT ALL TIMES.
• Some of the metals may not completely react; DO NOT POUR THEM DOWN THE SINK.
Instead, pour them in the specially marked waste beakers.
Procedure
1.
Use the glass marker to label each test tube with the symbol for each metal used in the lab.
Place the test tubes in a test-tube rack.
2.
One at a time, place the appropriate metal in each test tube. Using a small graduated cylinder,
carefully measure and pour 5 mL of hydrochloric acid into each of the five test tubes.
CP Chemistry
3.
Theodore Roosevelt High School
Lab #1-6
Observe what happens to the metal in each test tube and feel each test tube as the reaction
proceeds. Record your observations.
Additional Clean-up and Disposal
1.
Pour any leftover acid or metals into the appropriately marked waste beaker, i.e. pour the “Fe” test
tube into the “Fe” waste beaker.
Data – you should create a data table in your lab write-up that looks something like this:
Metal
Observations
Reactivity Rank
Aluminum
(Al)
Copper
(Cu)
…etc. for all metals.
Questions
1.
The rate at which hydrogen gas is produced as a result of these single-replacement reactions is
an indication of the relative reactivity of the metals. List the metals in order of their reactivity from
the most reactive to the least reactive.
2.
Were these reactions endothermic or exothermic? Explain.
3.
What could you do to determine whether the gas produced by these reactions is hydrogen?
Errors
Describe two possible errors you may have committed in this lab that may have somehow affected your
results. Explain the specific steps you will take to avoid each of these errors in the future.
Conclusion
Write two or more paragraphs summarizing your results, examining the validity of your prediction, and
explaining the reactivity of each metal.
CP Chemistry
Theodore Roosevelt High School
Reactivity of Metals Lab workspace:
Lab #1-6
CP Chemistry
Theodore Roosevelt High School
Lab #1-7
Activity Series of Metals – Capstone Lab
Introduction
Galvanic cells (or “batteries”) consist of two chambers separated by a semipermeable membrane. Each chamber consists of a metal electrode immersed
in a solution of one of its salts. A similar device can be created using citrus
fruit: each metal electrode is placed in a solution of citric acid, which reacts
with the electrodes to produce a little hydrogen gas and a surrounding solution
of that metal's salt, and numerous semi-permeable membranes in the fruit.
This galvanic cell will produce the voltage listed in chemical tables for
"electrochemical reduction potentials."
In this lab, you will determine the electrochemical production potentials of various metals using citrus
fruit and a multimeter. Based on your observations, you will then rank the metals by reactivity and
compare it to their known ranking in your textbook.
Purpose
To determine the activity series of metals using fruit.
Equipment
Determine all equipment you will use and list it in your lab write-up.
Materials
Determine all materials you will use and list them in your lab write-up.
Safety Considerations
• None for this lab beyond standard lab safety procedures.
Procedure
As you perform the lab, record your procedure steps, and then describe them in your lab write-up.
Data
Record all pertinent data and include it in your lab write-up.
Errors
Describe two possible errors you may have committed in this lab that may have somehow affected your
results. Explain the specific steps you will take to avoid each of these errors in the future.
Conclusion
Write two or more paragraphs summarizing and explaining your results, as well as critically analyzing
your procedure methods.
CP Chemistry
Theodore Roosevelt High School
Activity Series of Metals Capstone Lab workspace:
Lab #1-7
2
nd
Quarter
Laboratory Activities
CP Chemistry
Theodore Roosevelt High School
Lab #2-0
Stations Lab: Scientific Measurement
Introduction
Every measurement has an uncertainty, or built-in error. This error is due to
limitations in the measurement scale, the manufacturing process, and the ability of
the human eye to detect small differences. For example, when measuring volume
with a graduated cylinder, the width of the scale lines, variations in glass
thickness, and slight changes in your angle of sight when reading the scale are
just some of the factors that can cause uncertainty. Because of this uncertainty,
no measurement made in science should be thought of as an exact value, but
rather as a value within a range that varies with the uncertainty.
Purpose
To become familiar with the measurement scale of electronic balances, graduated cylinders, and rulers;
to make several different kinds of measurements and compare the uncertainty between them.
Equipment
balances (0.1, 0.01, and 0.001)
ball
beaker (100 mL and 250 mL)
Erlenmeyer flask (125 mL)
Materials
Chemistry textbook
pre-1982 pennies
graduated cylinder (10 mL and 100 mL)
meter stick
ruler
SmartBoard w/projector
silicon metal
Safety Considerations
• Sometimes chemicals from previous labs still remain in glassware and on other lab equipment.
Wash all lab equipment before performing this lab.
Procedure
Station A – Length
1.
Using a ruler, measure and record the length, width and height of a lab station in centimeters.
Repeat this measurement with a meter stick and record.
2.
Using a ruler, measure and record the length, width and height of a Chemistry textbook in
centimeters. Repeat this measurement with a meter stick and record.
3.
Using a ruler, measure and record the thickness of the pages of a Chemistry textbook (not the
covers). Count and record the number of pages you measured.
4.
Using a meter stick, measure and record the width, length and height of the Chemistry classroom
in meters.
Station B – Mass
1.
Obtain a piece of silicon metal that is small enough to fit inside a graduated cylinder. Weigh the
piece once on each of the three balances and record the measurement for each balance. Save
this piece for use at Station C.
2.
Obtain a pre-1982 penny. Weigh it once on each of the three balances and record the
measurement for each balance.
CP Chemistry
3.
Theodore Roosevelt High School
Lab #2-0
Obtain nineteen more pre-1982 pennies, for a total of twenty. Using a beaker, weigh them once
on the 0.01 balance and record.
Station C – Volume
1.
Obtain a pre-1982 penny. Using a ruler, measure and record the width and thickness of the
penny.
2.
Fill a 100-mL graduated cylinder with exactly 50-mL of tap water (be sure the bottom of the
meniscus, or curve of the water, is exactly on the 50 mL line). Place the penny in the water and
record the new volume. Dump out the water in the sink.
3.
Repeat step 2 with 20 pennies and record.
4.
Repeat step 2 with the small piece of silicon metal from Station B and record.
5.
Fill a 100-mL beaker to the 50-mL line with tap water. Pour this water into your graduated
cylinder and record. Dump out the water in the sink.
6.
Repeat step 5 with a 250-mL beaker and a 125-mL Erlenmeyer flask.
Station D – Accuracy & Precision
1.
At the SmartBoard, obtain a ball. Step back about ten feet and throw your ball at the center of the
target on the board (you may want to have your partner retrieve the ball for you to speed up the
process). DO NOT THROW THE BALL TOO HARD – IT COULD DAMAGE THE
SMARTBOARD. Repeat for a total of ten times, aiming at center of the target. Draw your target
results in the data table below as X’s.
2.
Using the eraser, remove all the marks on the SmartBoard target. Repeat step 1, except instead
of aiming for the center of the target, aim for the upper-right corner. After throwing the ball ten
times, draw your target results in the data table below as O’s.
3.
Repeat step 2, except instead of aiming at a particular point in the target, throw the ball ten times
with your eyes closed. Draw your target results in the data table below as ‘s and erase the
target before leaving.
Additional Clean-up and Disposal
1.
Dry the silicon metal and return it to its container
2.
Dry the pennies and return them to their container.
3.
Return the meter stick to the side table.
Data Table A – Length
Measurement
Length (cm)
Width (cm)
Thickness (cm)
# pages
Lab station
w/ruler
Lab station
w/meter stick
Textbook
w/ruler
Textbook
w/meter stick
Room 207
w/meter stick
Measurement
Book pages
w/ruler
Height (cm)
CP Chemistry
Theodore Roosevelt High School
Data Table B – Mass
Measurement
Mass (g)
Mass (g)
Mass (g)
0.1 balance
0.01 balance
0.001 balance
Thickness (cm)
Volume (cm3 or mL)
Silicon
One penny
20 pennies
Data Table C – Volume
Measurement
Width (cm)
One penny
20 pennies
Silicon
100-mL beaker
250-mL beaker
125-mL flask
Data Table D – Accuracy & Precision
Lab #2-0
CP Chemistry
Theodore Roosevelt High School
Lab #2-0
Calculations
1.
Calculate the volume of your lab station using your ruler data. Repeat this calculation with your
meter stick data.
2.
Calculate the volume of your textbook using your ruler data. Repeat this calculation with your
meter stick data.
3.
Calculate the volume of the classroom using your meter stick data.
4.
Using your textbook pages data, calculate the thickness of one page of your book.
5.
Using the combined mass of twenty pennies, determine the average mass of one penny.
Calculate the percent error of this average based on the accepted mass of pre-1982 pennies of
3.11 g.
6.
Using the width and thickness of a penny, calculate its volume using the equation V = πr2t, where
r is radius and t is thickness. Using the combined volume of twenty pennies, calculate the
average volume of one penny. Calculate the percent error for these two values using the
accepted volume of a pre-1982 penny of 0.3516 cm3.
7.
Using your mass and volume measurements of zinc, calculate its density. Calculate the percent
error using the accepted density of silicon of 2.329 g/cm3.
CP Chemistry
8.
Theodore Roosevelt High School
Lab #2-0
Using your volume measurements for the beakers and flask, calculate the percent error for each
compared with the accepted value of 50.0 mL.
Questions for discussion
1.
How different were the measurements made on the three balances? Which balance do you think
would be the best to use in lab activities? Why?
2.
The method of determining the volume of an object by submerging it in water is called “volume
displacement”. Identify one advantage and one disadvantage for this method.
3.
What did you find to be true about the accuracy of the markings on the sides of beakers and
flasks?
Errors
Think of two possible errors you may have committed in this lab that may have somehow affected your
results and record them below. Explain the specific steps you will take to avoid each of these errors in
the future.
1.
2.
Conclusion
Describe what you learned while doing this lab:
CP Chemistry
Theodore Roosevelt High School
Lab #2-1
SI Scavenger Hunt Lab
Introduction
According to the National Institute of Standards and Technology, the
International System of Units, universally abbreviated SI (from the
French Le Systéme International d’Unités), is the modern metric system
of measurement. Long the dominant system used in science, the SI is
rapidly becoming the dominant measurement system used in
international commerce. In recognition of this fact along with the
increasingly global nature of the marketplace, the Omnibus Trade and Competitiveness Act of 1988
designated “the metric system of measurement as the preferred system of weights and measures for
United States trade and commerce.” As a result, SI is expected to be increasingly used in areas other
than science throughout America for the foreseeable future.
Purpose
To become familiar with SI units, measurement, and conversion.
Prediction
What would you predict the dimensions of the classroom are (length x width) in meters?
Equipment
electronic balance
graduated cylinder (100 mL)
meter stick
ruler
Materials
various (see procedure)
Safety Considerations
• None for this lab beyond standard lab safety procedures.
Procedure:
Part A – Length
1.
Determine the length of a teammate's foot, in meters.
2.
Determine the width of the classroom, in centimeters.
3.
Determine the thickness of a calculator, in millimeters.
4.
Find a person in the class who is approximately 1.6 meters tall and determine his or her exact
height, in millimeters.
Part B – Volume
1.
Determine the volume of a paperback book, in cm3.
2.
Determine the volume of one coin, in mm3.
3.
Determine the volume of a piece of jewelry, in mL.
4.
Find an object with a volume of around 100 cm3 and determine its volume, in cm3.
CP Chemistry
Theodore Roosevelt High School
Lab #2-1
Part C – Mass
1.
Determine the mass of a dollar bill, in grams.
2.
Determine the mass of a ring, in centigrams.
3.
Determine the mass of a piece of chalk, in milligrams.
4.
Find a single object different from those already used that has a mass between 100 and 200
grams and determine its mass, in grams.
5.
Find a single object different from those already used that has a mass between 10 and 25 grams
and determine its mass, in grams.
Part D – Density
1.
Determine the density of a coin, in g/mL.
2.
Determine the density of a piece of jewelry, in g/cm3.
3.
Find a single object different from those already used that is more dense than water and
determine its density, in g/mL.
Data – you should create a data table in your lab write-up that looks something like this:
Station
Measurement
Calculation Result
A1
A2
Calculations
A1. Calculate the length of your teammate’s foot in decimeters.
A2. Calculate the width of the classroom in millimeters.
A3. Calculate the thickness of the calculator in meters.
A4. Calculate the height of the person measured in Procedure A4 in micrometers.
B1. Calculate the volume of the paperback book in milliliters.
B2. Calculate the volume of the coin in cm3.
B3. Calculate the volume of the piece of jewelry in microliters.
B4. Calculate the volume of the object measured in Procedure B4 in Liters.
C1. Calculate the mass of the dollar bill in milligrams.
C2. Calculate the mass of the ring in kilograms.
C3. Calculate the mass of the piece of chalk in grams.
C4. Calculate the mass of the object measured in Procedure C4 in micrograms.
C5. Calculate the mass of the object measured in Procedure C5 in decigrams.
D1. Calculate the density of the coin in g/L.
D2. Calculate the density of the piece of jewelry in kg/mL.
D3. Calculate the density of the object measured in Procedure D3 in kg/L.
Questions
1.
What method did you use to determine the volume of jewelry used in Procedure B3? Why did you
use this method?
2.
What method did you use to determine the density of the coin used in Procedure D1? Why did
you use this method?
3.
Do you find it difficult to use SI units as compared to American customary units? Why or why not?
CP Chemistry
Theodore Roosevelt High School
Lab #2-1
Errors
Describe two possible errors you may have committed in this lab that may have somehow affected your
results. Explain the specific steps you will take to avoid each of these errors in the future.
Conclusion
Write two or more paragraphs summarizing your results, examining the validity of your prediction, and
describing what you learned while doing this lab.
CP Chemistry
Theodore Roosevelt High School
SI Scavenger Hunt Lab workspace:
Lab #2-1
CP Chemistry
Theodore Roosevelt High School
Lab #2-2
Density Blocks Lab
Introduction
All measurements involve some degree of error or estimation. The
measurements are based on the fact that the human eye can estimate to onetenth of the smallest mark shown on a measuring instrument. Therefore, a ruler
with only 1-cm increments shown can provide measurements that are estimated
to 0.1 cm, while a ruler with 0.1-cm increments shown can provide
measurements that are estimated to 0.01 cm.
In this lab, you will take the measurement challenge by first determining the
volume of a plastic block, and then predict its mass using the known density of
that block. Success in this challenge depends on your ability to take accurate measurements!
Purpose
To practice the calculation of density while demonstrated both accurate and precise measurement
skills.
Prediction
Can density be used to identify an unknown substance? Explain.
Equipment
balance
ruler
Materials
plastic blocks, 4
Safety Considerations
• None for this lab beyond standard lab safety procedures.
Procedure & Calculations
Part 1 – Density Calculation
1.
Obtain a plastic block from your teacher; record the block number and color of the block.
2.
Using the electronic balance, measure and record the mass of the block.
3.
Using a ruler, measure and record the dimensions of the block.
4.
Calculate the volume of the block, showing all work.
5.
Calculate the density of the block, showing all work.
6.
Repeat steps 1-5 for two additional blocks, being sure to obtain blocks of different colors.
Part 2 – The Measurement Challenge
1.
Obtain a plastic block from your teacher. Record the block number and color of the sample. The
block number must be different from any of the block numbers used in Part 1.
2.
Using a ruler, measure and record the dimensions of the block.
3.
Using the known densities provided in the table below, calculate the theoretical mass of the
plastic block.
CP Chemistry
Theodore Roosevelt High School
Density
(g/cm3)
0.541
0.985
0.908
1.18
1.42
Block Color
white
black
milky-white
clear
gray
4.
5.
Lab #2-2
After predicting the mass of the block, take it to your teacher, who will measure its mass for you
using a high-precision balance. Record this value in your data table.
Determine the accuracy of your mass calculation by calculating the percent error between your
predicted mass and the actual mass of the plastic block.
Data – you should create a data table in your lab write-up that looks something like this:
Block # and Color
Length
Height
Width
Mass
Volume*
Density*
8 - Grey
11 - Clear
Questions
1.
How did you use density to identify an unknown substance?
2.
Do you think you could accurately use volume displacement to determine the volume of these
plastic blocks? Why or why not?
3.
Identify two things you learned about density as a result of this lab activity.
Errors
Describe two possible errors you may have committed in this lab that may have somehow affected your
results. Explain the specific steps you will take to avoid each of these errors in the future.
Conclusion
Write two or more paragraphs summarizing your results, examining the validity of your prediction, and
explaining your calculations.
CP Chemistry
Theodore Roosevelt High School
Density Blocks Lab workspace:
Lab #2-2
CP Chemistry
Theodore Roosevelt High School
Lab #2-3
Atomic Mass of “Beanium” Lab
Introduction
On the periodic table, values for atomic number and atomic mass are
given for each element. The atomic number is a whole number that
represents the number of protons in the atom. The atomic mass is a
decimal number because it represents a weighted average of the
masses of the isotopes of each element based on how often each
isotope is found in nature.
Nuclear chemists have discovered what is believed to be element number 119. The researchers have
named this element “Beanium”. There are three naturally occurring isotopes of beanium: beaniumwhite, beanium-brown, and beanium-green. Your job is to determine the atomic mass of each individual
isotope, the percentage abundance of each isotope, and ultimately the average atomic mass of
beanium. One unique property of beanium that should make this determination particularly easy is that
beanium atoms are very large, so sorting the isotopes of this element should be accomplished with little
difficulty.
Purpose
To determine the average atomic mass for the fictitious element “beanium”.
Prediction
In this lab, you will determine the average mass of all the beans together, and then the average mass
of each type of bean based in their abundance. How close do you think these values will be to each
other?
Equipment
balance
beaker (100 mL)
Materials
beans, various types
Safety Considerations
• None for this lab beyond standard lab safety procedures.
Procedure
1.
Obtain a sample of beanium isotopes by scooping up a beaker full of beans from the bean
container.
2.
Separate the beans by isotope and count them. Record the total number of each type of bean.
3.
For each isotope sample of beanium, determine and record its total mass.
4.
Determine and record the total mass of your entire sample of beanium.
5.
For each isotope, calculate its average mass by dividing the total mass of that isotope by the
number of beans of that isotope.
6.
For each isotope, calculate its percent abundance by dividing the number of beans in each
isotope by the total number of beans.
7.
Calculate the total % abundance of beanium isotopes by summing their abundances.
CP Chemistry
8.
9.
Theodore Roosevelt High School
Lab #2-3
Calculate the average atomic mass of beanium by dividing the total mass of the entire sample by
the total number of beans.
Calculate the average atomic mass of beanium again by first multiplying each isotope’s average
mass by its percent abundance and then adding these values together.
Additional Clean-up and Disposal
1.
Return your beanium sample to the bean container. DO NOT LEAVE ANY BEANS IN THE SINK
OR AT YOUR LAB STATION.
Questions
1.
What is an isotope? How is it related to beanium?
2.
Compare your average mass of beanium with that of two other groups. How does your average
mass compare to theirs? Why do you think this happened?
3.
Neon-20 has a mass of 19.9924 amu, neon-21 has a mass of 20.9940 amu, and neon-22 has a
mass of 21.9914 amu. The relative abundance of Ne-20 is 90.92%, while Ne-21 is 0.257% and
Ne-22 is 8.82%. Using the same techniques that you used in this lab, calculate the average
atomic mass for neon. How does this compare to the value for neon found on the periodic table?
Errors
Describe two possible errors you may have committed in this lab that may have somehow affected your
results. Explain the specific steps you will take to avoid each of these errors in the future.
Conclusion
Write two or more paragraphs summarizing your results, examining the validity of your prediction, and
explaining your calculations.
CP Chemistry
Theodore Roosevelt High School
Atomic Mass of “Beanium” Lab workspace:
Lab #2-3
CP Chemistry
Theodore Roosevelt High School
Lab #2-4
Composition of a Penny Lab
Introduction
As you know, the United States one-cent coin, or the penny, is a unit of
currency equaling one one-hundredth of a United States dollar. However,
you may not know that the composition of the penny has changed
dramatically over the years. In 1943, at the peak of World War II, cents of
zinc-coated steel were made for a short time due to war demands for
copper. During the early 1970s, the price of copper rose to a point where
the cent almost contained more than one cent's worth of copper. This led
the Mint to test alternate metals, including aluminum and bronze-clad
steel, though neither were adopted. Because the value of the copper in the coin eventually rose above
one cent, the cent's composition was finally changed in 1982 to its current make-up of an inside zinc
core surrounded by a thin copper coating.
In this lab, we will determine the percent composition of a modern (post-1982) penny by using a strong
acid to react and dissolve the zinc core, leaving only the copper coating. Once only copper remains,
we will compare its mass to the entire mass of the penny to determine how much of a penny is copper
and how much is zinc.
Purpose
To practice calculating percent composition.
Prediction
What percentage of your penny do you think will be made of zinc? Why do you think so?
Equipment
beaker, 100 mL
metal file
oven
Materials
hydrochloric acid, 1M [HCl]
penny (1983 or later)
Procedure
Day 1:
1.
Obtain a clean post-1982 penny.
2.
Measure and record the mass of the penny in your lab notebook.
3.
Using a metal file, file three, oppositely-placed small grooves into the edge of the penny. The
grooves must be deep enough so that the zinc is exposed, but not so deep that the penny's mass
is greatly affected.
4.
Obtain a small beaker and label it with your name, your partner’s name and your period.
5.
While wearing gloves, carefully pour 75 mL of 1M HCl into a 100-mL beaker.
6.
Carefully place the penny in the acid. Observe the effect the acid has on the copper outside of
the penny.
7.
Place your labeled beaker under either fume hood to react overnight.
CP Chemistry
Theodore Roosevelt High School
Lab #2-4
Day 2:
1.
After the penny has reacted overnight, carefully pour some water from another beaker into the
acid to dilute it.
2.
Carefully remove the remainder of the penny with a pair of tongs.
3.
Gently rinse the penny with water from a wash bottle and pat it dry with paper towels.
4.
If any zinc inside the penny remains unreacted, repeat steps #5-7 from Day 1 and check again the
next day.
5.
Put the penny in a small beaker and place it in the oven for 5-10 minutes to allow it to dry
completely.
6.
Dispose of the acid in the large waste beaker in the fume hood (DO NOT POUR IT DOWN THE
SINK).
7.
Remove the penny and measure and record its new mass in your lab notebook.
8.
Dispose of the penny in the trash and clean all used glassware.
Data – you should create a data table in your lab write-up that looks something like this:
Day 1 Mass
Day 2 Mass
Mass of Zinc*
% Composition*
% Error*
Calculations
1.
Calculate the mass of zinc in the penny that was reacted.
2.
Knowing the total mass of the penny and the mass of both copper and zinc in the penny, calculate
the percent composition of your penny.
3.
According to the United States Mint, pennies are 97.5% zinc and 2.5% copper. Calculate the
percent error for your experimental percent composition of zinc.
4.
Using the accepted density of zinc (7.140 g/cm3) and the accepted volume of a penny
(0.360 cm3), calculate what the mass of a penny would be if it were made of solid zinc.
Questions
1.
Why is the mass of your penny so close to the mass of the hypothetical “solid zinc penny”
calculated in Calculation #4?
2.
Copper and zinc are next to each other on the period table. How is it possible that one of them
would react with hydrochloric acid, but not the other?
3.
Why is it necessary to use a post-1982 penny for this lab?
Errors
Describe two possible errors you may have committed in this lab that may have somehow affected your
results. Explain the specific steps you will take to avoid each of these errors in the future.
Conclusion
Write two or more paragraphs summarizing your results, examining the validity of your prediction, and
describing what you learned while doing this lab.
CP Chemistry
Theodore Roosevelt High School
Composition of a Penny Lab workspace:
Lab #2-4
CP Chemistry
Theodore Roosevelt High School
Lab #2-5
Stoichiometry Lab
Introduction
In chemical reactions, the actual masses of substances used are
proportional to their molar masses. Therefore, it’s possible to predict the
number of grams of a given product that will be formed in a reaction if you
know the mass of any one of the reactants.
In this lab, you will start with a known mass of basic copper (II) carbonate and determine the mass of
copper (II) oxide formed by decomposition due to heat. Using stoichiometry, you will then calculate the
theoretical mass of copper (II) oxide that should form in this reaction. The difference between the
actual yield obtained from the experiment and the theoretical yield calculated using stoichiometry can
then be used to determine the percent error and percent yield of your product.
Purpose
To use stoichiometry to calculate the theoretical mass for the product of the reaction and compare it to
the actual yield using percent error and percent yield.
Prediction
Do you think you will be able to achieve 100% yield with this lab? Explain.
Equipment
balance
Bunsen burner
clay triangle
evaporating dish
iron ring
ring stand
stirring rod
tongs
Materials
copper (II) carbonate, basic [CuCO3·Cu(OH)2 (s)]
Safety Considerations
• Basic copper (II) carbonate is TOXIC, with a lethal dose of 140 mg per kg of body mass. This
means that a 125-lb. student could die from ingesting as little as 8 grams. Avoid contact with
basic copper (II) carbonate and wash your hands after completing the lab!
• Safety goggles must be worn at all times.
• Sometimes chemicals from previous labs still remain in glassware and on other lab equipment.
Wash all lab equipment before and after performing this lab.
Procedure
1.
Determine the mass of a clean evaporating dish. Record this value.
2.
Obtain as close to one gram of basic copper (II) carbonate as possible and determine its mass.
Record this value in a data table.
3.
Add the basic copper (II) carbonate to the empty evaporating dish.
4.
Place the evaporating dish on the clay triangle supported by the ring stand. Heat the evaporating
dish using the Bunsen burner until all of the basic copper (II) carbonate has been converted to
black copper (II) oxide. You may want to stir the materials toward the end of heating to make sure
all the reactant has decomposed, but be careful not to allow anything to stick to your stirring rod.
CP Chemistry
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Theodore Roosevelt High School
Lab #2-5
After you have finished heating, CAREFULLY remove the evaporating dish with tongs and gently
place it on your lab station to cool. If you drop your evaporating dish and spill your product, you
will have to start the lab over from the beginning.
Once the evaporating dish has cooled enough to touch, determine the mass of the dish and the
contents together and determine the actual yield of copper (II) oxide. Record this value.
Additional Clean-up and Disposal
1.
Dispose of the black copper (II) oxide in the marked waste beaker, NOT the trash can.
Calculations (Use your answers in your conclusion!)
1.
Using the data from Procedure #1 and Procedure #6, calculate the amount of copper (II) oxide
you produced.
2.
Use stoichiometry to calculate the theoretical yield of copper (II) oxide; the mass of basic copper
(II) carbonate you recorded is your “given”. Use the following balanced chemical equation:
∆ 2 CuO (s) + CO (g) + H O (g)
CuCO3·Cu(OH)2 (s) →
2
2
3.
Compare your actual yield of copper (II) oxide in Calculation #1 to the theoretical yield in
Calculation #2 by calculating the percent yield and percent error for your reaction using these
equations:
Questions
1.
In the reaction we saw in this lab, would you expect your solid product (copper (II) oxide) to have
a greater, equal, or smaller mass than the reactant? Why?
2.
What relationship did you notice between percent yield and percent error? Describe a situation
for each where one value may be more useful than the other.
3.
Based on your observations of green basic copper (II) carbonate during this lab and drawing from
your previous experiences with blue copper (II) sulfate pentahydrate crystals, what general
conclusion can you draw about other hydrates such as these?
Errors
Describe two possible errors you may have committed in this lab that may have somehow affected your
results. Explain the specific steps you will take to avoid each of these errors in the future.
Conclusion
Write two or more paragraphs summarizing your results, examining the validity of your prediction, and
explaining your calculations.
CP Chemistry
Theodore Roosevelt High School
Stoichiometry Lab workspace:
Lab #2-5
CP Chemistry
Theodore Roosevelt High School
Lab #2-6
Limiting Reagents Lab: Turning Iron into Copper
Introduction
As we’ve seen before, it’s possible to predict the number of grams of a
given product that will be formed in a chemical reaction if you know the
mass of any one of the reactants. In this lab, you will start with known
masses of copper (II) sulfate and iron and determine the mass of copper
metal formed by a chemical reaction. However, one of these chemicals
will be completely used up by the reaction – the limiting reagent – and
the other will not, leaving some chemical left over in excess.
Because this reaction could also form either iron (II) sulfate or iron (III)
sulfate, you will use both observations and stoichiometry to determine
the chemical reaction that occurred. Through calculations, you will also
determine the theoretical mass of copper metal that should form from this
reaction and determine its percent yield.
Purpose
To use stoichiometry calculations to calculate theoretical mass and percent yield.
Prediction
Which reactant – copper (II) sulfate or iron – will be the limiting reagent? Explain why you think so.
Equipment
balance
beaker, 250 mL
Bunsen burner
iron ring
permanent marker
ring stand
stirring rod
wire gauze
Materials
copper (II) sulfate (anhydrous) [CuSO4 (s)]
distilled water
filter paper
iron filings [Fe (s)]
Safety Considerations
• Safety goggles must be worn at all times.
• Sometimes chemicals from previous labs still remain in glassware and on other lab equipment.
Wash all lab equipment before and after performing this lab.
Procedure
1.
Measure 7.00 g of anhydrous copper (II) sulfate and place it in a 250 mL beaker.
2.
Add about 50 mL of distilled water and heat gently over a Bunsen burner until the solid has
completely dissolved. DO NOT ALLOW THE SOLUTION TO BOIL.
3.
Once the crystals have dissolved, remove the beaker from the heat. Record your observations of
the solution’s appearance.
4.
Measure 2.00 g of iron filings and slowly add them to the beaker while stirring the hot CuSO4
solution.
CP Chemistry
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Theodore Roosevelt High School
Lab #2-6
Allow this solution to sit for at least 10 minutes. Record your observations of the solution’s
appearance.
Obtain a piece of filter paper and label it with your lab group members’ names using a permanent
marker. Determine and record its mass.
Fold the filter paper in quarters and place it in a funnel, wetting it with distilled water to keep it in
place.
Filter the solution through the funnel and filter paper to collect the copper product. Wash the
product with distilled water. Let the filter paper and copper sit overnight.
After allowing the filter paper to dry overnight, determine and record its mass.
Additional Clean-up and Disposal (after the 2nd day)
1.
Dispose of the copper product in the waste beaker, NOT the trash can.
2.
Dispose of the filter paper in the trash.
Data – you should create a data table in your lab write-up that looks something like this:
Item
Mass (g)
unused filter paper
Calculations (Include these answers in your Conclusion!)
1.
One possible unbalanced chemical equation for this reaction is:
copper (II) sulfate (aq) + iron (s) → copper (s) + iron (II) sulfate (aq)
If this were the correct reaction, what mass of copper should be produced in this lab?
2.
The other possible unbalanced chemical equation for this reaction is:
copper (II) sulfate (aq) + iron (s) → copper (s) + iron (III) sulfate (aq)
If this were the correct reaction, what mass of copper should be produced in this lab?
3.
What mass of copper was formed? What was the percent yield of this reaction?
Questions
1.
What are some of the clues you observed that suggested a chemical reaction occurred?
2.
Which reactant limited the reaction? What observations support this conclusion?
3.
Based on your data, which product was formed along with the copper metal: iron (II) sulfate or
iron (III) sulfate? How do you know?
Errors
Describe two possible errors you may have committed in this lab that may have somehow affected your
results. Explain the specific steps you will take to avoid each of these errors in the future.
Conclusion
Write two or more paragraphs summarizing your results, examining the validity of your prediction, and
explaining your calculations.
CP Chemistry
Theodore Roosevelt High School
Limiting Reagents Lab workspace:
Lab #2-6
CP Chemistry
Theodore Roosevelt High School
Lab #2-7
Bulbous Balloon Challenge – Capstone Lab
Introduction
It’s pretty likely that you’ve seen the classic science fair reaction
between vinegar and baking soda that’s used in model volcanoes. A
similar reaction occurs between vinegar and the calcium carbonate in
antacids to produce carbon dioxide gas:
acetic acid (vinegar)+ calcium carbonate →
carbon dioxide + calcium acetate + water
Your task is to determine how many antacids are needed to produce
exactly 500 mL of carbon dioxide gas. To maintain consistency, you should use 100 mL of vinegar for
each trial. Since antacids contain sugars, coloring and other inactive ingredients, in order to calculate
the necessary amount of antacid, you will also have to determine the percent composition of calcium
carbonate in the antacid by reading its label. The most difficult task of all will be to determine how
you’re going to measure the carbon dioxide gas that is produced!
Purpose
To determine how many antacids are necessary to produce 500 mL of gas when reacted with 100 mL
of vinegar.
Equipment
Determine all equipment you will use and list it in your lab write-up.
Materials
Determine all materials you will use and list them in your lab write-up.
Safety Considerations
• None for this lab beyond standard lab safety procedures.
Procedure
As you perform the lab, record your procedure steps, and then describe them in your lab write-up.
Data
Record all pertinent data and include it in your lab write-up.
Errors
Describe two possible errors you may have committed in this lab that may have somehow affected your
results. Explain the specific steps you will take to avoid each of these errors in the future.
Conclusion
Write two or more paragraphs summarizing and explaining your results, as well as critically analyzing
your procedure methods.
CP Chemistry
Theodore Roosevelt High School
Bulbous Balloon Challenge Capstone Lab workspace:
Lab #2-7
rd
3 Quarter
Laboratory Activities
CP Chemistry
Theodore Roosevelt High School
Lab #3-0
Gas Laws: Stations Lab
Introduction
Scientists have been examining the properties of gases for hundreds of years. They
are responsible for many of the earliest theories and discoveries in chemistry, including
the first model of the atom. In this lab, we will use a variety of methods to observe the
relationships in gases between pressure, temperature, volume and moles.
Purpose
To observe the effects of changes in pressure, temperature and volume on gases.
Materials
aluminum cans, empty
balloons
ice
tap water
Equipment
beaker tongs
beakers, 1000-mL, 2
Bunsen burner
dropper
electronic balance, 0.001g
Erlenmeyer flasks, 125-mL, 2
hot plates, 2
netbook or laptop
plastic tray
stopper, one-hole
syringe, 20-cc
vacuum apparatus
Vernier gas pressure sensor
Vernier LabQuest
2-Liter bottle
Safety Considerations
• Wash your hands thoroughly after completing this lab.
Procedure
For each of the following stations, follow the directions and record your observations in the data
table. You may complete the stations in any order.
Station A – Cartesian Diver
1.
If it is empty, fill the 2-Liter bottle completely full with tap water and replace the cap.
2.
Squeeze the sides of the bottle and observe the “Cartesian diver” inside.
Station B – Pressure Sensor and Syringe
1.
Disconnect the syringe by unscrewing it from the plastic valve.
2.
Adjust the plunger in the syringe until it is at 10cc. Reconnect the syringe to the valve and record
the initial pressure displayed on the Vernier LabQuest.
3.
Push the plunger in until it is at 5cc. Record the resulting pressure.
4.
Pull the plunger out until it is at 20cc. Record the resulting pressure.
Station C – Balloon and Water Baths
1.
Make sure that the balloon is securely attached to the mouth of the Erlenmeyer flask.
2.
Carefully place the flask in the hot water bath. Observe any changes that occur after one minute.
3.
Remove the flask and carefully place it in the ice water bath. Observe any changes that occur
after one minute.
4.
Return the flask to the lab station for the next group.
Station D – Balloon Animals vs. Liquid Nitrogen
1.
Watch the video titled “Balloons in Liquid Nitrogen” by double-clicking on it. You can watch the
video in fullscreen mode by pressing the “F” key.
CP Chemistry
Theodore Roosevelt High School
Lab #3-0
Station E – Can Crusher
1.
Obtain an empty aluminum pop can and add a very small amount of tap water (<5 mL) to the can.
2.
Using beaker tongs, heat the bottom of the can in a Bunsen burner flame until you hear a
bubbling or sizzling sound.
3.
Very quickly but carefully, turn the can upside down and place it in the shallow ice water bath so
that the mouth is completely underwater.
4.
Empty the used can in the sink and then place it in the recycling bin.
Station F – Mass of Air
1.
Obtain an empty balloon and weigh it on the electronic balance. Record the initial mass.
2.
Inflate the balloon by blowing into it and tie it off.
3.
Weigh the inflated balloon and record its final mass. You may discard the balloon or take it with
you.
Station G – Pressure Sensor and Water Baths
1.
Make sure the stopper is firmly in the mouth of the Erlenmeyer flask and record the initial pressure
displayed on the Vernier LabQuest.
2.
Carefully place the flask in the hot water bath. Record the resulting pressure after one minute.
3.
Remove the flask and carefully place it in the ice water bath. Record the resulting pressure after
one minute.
4.
Return the flask to the lab station for the next group.
Station H – Marshmallow and Vacuum Pump
1.
DO NOT EAT THE MARSHMALLOWS.
2.
Obtain a marshmallow and place it inside the bell jar of the vacuum pump apparatus. Make sure
the apparatus is sealed and the valve is set correctly.
3.
Pull on the syringe plunger several times until you see a noticeable change in the marshmallow.
4.
Turn the valve so you can open the bell jar and discard the marshmallow.
CP Chemistry
Theodore Roosevelt High School
Lab #3-0
Data – record your data in the table below:
Station
Observations
Station A
Station B
Station C
Station D
Station E
Station F
Station G
Station H
Questions for discussion
1.
For Stations A, B and H, explain how pressure had an effect on each system.
2.
For Stations C, D and G, explain how temperature had an effect on each system.
3.
For Station E, what force crushed the can? Explain.
Errors
Think of two possible errors you may have committed in this lab that may have somehow affected your
results and record them below. Explain the specific steps you will take to avoid each of these errors in
the future.
1.
2.
Conclusion
Describe what you learned while doing this lab:
CP Chemistry
Theodore Roosevelt High School
Lab #3-1
Change of Physical State Lab
Introduction
In this lab, you will investigate the freezing behavior of the organic
compound lauric acid, CH3(CH2)10COOH. In any pure substance, changes
of physical state occur at constant, discrete temperatures that are uniquely
characteristic of the substance. You will use a Vernier LabQuest to measure
the temperature of lauric acid as it freezes over time and graph these data to
determine its freezing point.
Purpose
Based on the introduction above, determine the purpose of this lab and include
it in your lab write-up.
Prediction
Do you think the lauric acid will freeze quickly or will it take a long time? Why do you think so?
Equipment
beaker (400 mL)
large test tube w/wire stirrer
ring stand
utility clamp
Vernier LabQuest
Vernier temperature probe
Materials
lauric acid [CH3(CH2)10COOH] (in test tube)
tap water
Safety Considerations
• Lauric acid is mildly irritating – avoid contact with the skin and eyes.
• Safety goggles must be worn at all times.
• Sometimes chemicals from previous labs still remain in glassware and on other lab equipment;
wash all lab equipment before and after performing this lab.
• Wash your hands thoroughly after completing this lab.
Procedure
1.
Turn on the Vernier LabQuest and connect the temperature probe. Tap on the settings box on
the right of the sensor screen and set the collection time to 40 minutes and the frequency to 10
times per minute. Save the settings by tapping the “Done” button.
2.
Fill a 400 mL beaker with about 250 mL of cold tap water. Place the beaker on the lab counter
next to a ring stand.
3.
Attach a utility clamp to the ring stand and place it above the beaker.
4.
Obtain a large test tube with melted lauric acid and a wire stirrer from the hot water bath in the
back of the room. Place the large test tube in the beaker and hold it in place using the clamp.
Make sure the water level is above the level of the lauric acid in the test tube; add water to the
beaker if necessary.
5.
Place the temperature probe in the test tube, making sure it does not touch the glass, and begin
recording data by pressing the play button.
6.
Gently stir the lauric acid with the wire stirrer with constant motion. Continue stirring the lauric
acid throughout the experiment.
7.
Record the time at which the lauric acid started to freeze and the time when it was
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Theodore Roosevelt High School
Lab #3-1
completely frozen.
Continue stirring the lauric acid and recording temperature readings with the LabQuest until the
temperature of the material has fallen below 40°C. When most of the lauric acid has solidified,
you will no longer be able to stir the contents.
Return the lauric acid test tube to the hot water bath in the back of the room.
Using the LabQuest stylus, highlight as much of the flat section of the curve as possible. Record
the average of these data points (shown on the right) as the melting point of lauric acid.
Turn off the LabQuest (discard the data) and return it to the supplies table.
Additional Clean-up and Disposal
1.
Disconnect and clean the temperature probe with soap and water using a test tube brush.
Calculations (Include these answers in your Conclusion!)
1.
The accepted freezing point of lauric acid is 44.0°C. Using temperatures in Kelvins, calculate
your percent error for this lab.
Questions
1.
Based on your lab results, does the temperature of a substance vary while it is freezing? Explain
why or why not.
2.
Would increasing the amount of lauric acid used affect your curve? Explain why or why not.
3.
In this lab, you recorded temperature readings every 6 seconds. Between temperature and time,
which is the manipulated variable and which is the responding variable? Explain.
Errors
Describe two possible errors you may have committed in this lab that may have somehow affected your
results. Explain the specific steps you will take to avoid each of these errors in the future.
Conclusion
Write two or more paragraphs summarizing your results, examining the validity of your prediction, and
explaining your calculations.
CP Chemistry
Theodore Roosevelt High School
Change of Physical State Lab workspace:
Lab #3-1
CP Chemistry
Theodore Roosevelt High School
Lab #3-2
Calorimetry Lab
Introduction
Much like in the previous lab where we melted an ice cube, you can
use q = CmΔT to calculate the heat change that occurs when you
dissolve an ionic solid. You can then determine the molar heat of
solution, ΔHsoln, in kJ/mol by dividing the heat change by the moles of
chemical dissolved. Positive molar heats represent endothermic
changes, which cause a decrease in the temperature of the
surroundings, while negative molar heats have the opposite effect.
In this lab, you will compare the calculated heat change of each chemical to its accepted value to
determine your percent error. Be sure to work quickly, measure accurately and keep your calorimeter
lid secure to ensure the best possible data!
Purpose
Based on the introduction above, determine the purpose of this lab and include it in your lab write-up.
Prediction
During the winter, calcium chloride is used to melt ice from streets and sidewalks. Do you think this is
an endothermic or an exothermic reaction? Explain.
Equipment
beaker, 250 mL
cardboard lid
electronic balance, 0.01 g
graduated cylinder, 100 mL
Materials
ammonium chloride [NH4Cl]
Styrofoam cups, 2
Vernier LabQuest
Vernier temperature probe
calcium chloride [CaCl2]
Safety Considerations
• Safety goggles must be worn at all times.
• Sometimes chemicals from previous labs still remain in glassware and on other lab equipment;
wash all lab equipment before and after performing this lab.
• Wash your hands thoroughly after completing this lab.
Procedure
1.
Turn on the Vernier LabQuest and connect the temperature
probe. Tap on the settings box on the right of the sensor screen
and set the collection time to 10 minutes and the frequency to 60
times per minute (once per second). Save the settings by
tapping the “Done” button.
2.
Assemble your calorimeter per the diagram shown to the right.
3.
Using a graduated cylinder, measure out exactly 100.0 mL tap
water and pour it into your Styrofoam cup calorimeter.
4.
Using the LabQuest’s temperature probe, measure the starting
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Theodore Roosevelt High School
Lab #3-2
temperature of the water. Record this value.
Obtain approximately 5 g of calcium chloride. Using weigh paper, measure and record the
mass of the chemical.
Quickly place the calcium chloride in the calorimeter, securely replace the lid and begin recording
data on your LabQuest by pressing the play button.
Gently swirl the calorimeter to help the calcium chloride to dissolve completely and evenly; be
careful not to spill any water.
Once all of the chemical has dissolved, stop recording data on your LabQuest. Using the stylus,
select all of the data on the graph and then tap the ‘Analyze’ menu, then ‘Statistics’ and finally
‘Temperature’. Record the maximum value displayed on the right as the final temperature
of the water.
Clear the recorded data and perform steps 3-8 again using ammonium chloride instead of calcium
chloride, and record the minimum temperature instead of the maximum.
Data – you should create a data table in your lab write-up that looks something like this:
Chemical
Mass
Starting
Temp
Final
Temp
q*
ΔHsoln*
% error*
calcium chloride
Calculations (Include these answers in your Conclusion!)
1.
Knowing the number of moles of each chemical that were dissolved, and knowing the heat
change caused by each chemical (q), determine the molar heat of solution (ΔHsoln) for each
chemical in kJ/mol.
2.
The accepted heat of solution (ΔHsoln) of calcium chloride is -82.8 kJ/mol. Using your experimental
value for ΔHsoln of calcium chloride, calculate your percent error in this experiment.
3.
The accepted heat of solution (ΔHsoln) of ammonium chloride is +14.7 kJ/mol. Using your
experimental value for ΔHsoln of ammonium chloride, calculate your percent error in this
experiment.
Questions
1.
Why is the molar heat of solution (ΔHsoln) of calcium chloride a negative value? Why is the molar
heat of solution (ΔHsoln) of ammonium chloride a positive value?
2.
Compare your results to those of another lab group. Were their values for ΔHsoln similar to or
different from yours? Explain why or why not.
3.
How do you think you might apply this technique to determining the amount of chemical potential
energy stored in food?
Errors
Describe two possible errors you may have committed in this lab that may have somehow affected your
results. Explain the specific steps you will take to avoid each of these errors in the future.
Conclusion
Write two or more paragraphs summarizing your results, examining the validity of your prediction, and
explaining your calculations.
CP Chemistry
Theodore Roosevelt High School
Calorimetry Lab workspace:
Lab #3-2
CP Chemistry
Theodore Roosevelt High School
Lab #3-3
Heat of Combustion of a Candle Lab
Introduction
In the past several labs, we have used makeshift calorimeters with water to
measure the heat absorbed by or released from fusion, dissolution and
combustion. These setups have reflected temperature changes in the
correct direction (i.e., up or down) but have also had significant percent
error. In this lab, we will attempt to decrease our percent error by directly
measuring the difference between the heat released by burning a known
amount of paraffin wax and the heat absorbed by a known amount of water.
Purpose
Based on the introduction above, determine the purpose of this lab and include it in your lab write-up.
Prediction
Will the heat change for the combustion of paraffin have a positive or negative value? Explain.
Equipment
Erlenmeyer flask, 125 mL
graduated cylinder, 100 mL
ring stand
rubber stopper
Materials
matches
thermometer
tin can
utility clamp
paraffin candle [C25H52]
Safety Considerations
• Sometimes chemicals from previous labs still remain in glassware and on other lab equipment;
wash all lab equipment before and after performing this lab.
• Wash your hands thoroughly after completing this lab.
Procedure
1.
Obtain a candle; measure and record its mass.
2.
Measure out exactly 100.0 mL tap water into a 125-mL Erlenmeyer flask. Use a stopper with a
hole to seal the flask – make sure the number on the stopper matches the number on the flask!
3.
Using a ring stand, attach the flask to a utility clamp so that its bottom is 1-2 inches above the tin
can.
4.
Measure and record the starting temperature of the water.
5.
Away from the flask, use a match to light the candle and quickly slide it underneath the flask. DO
NOT PLACE USED MATCHES IN THE SINK.
6.
Allow the candle to burn for around 5 minutes or until the temperature of the water reaches 30°C,
whichever comes first.
7.
Gently blow out the candle and record the peak temperature of the water.
8.
Allow the candle to cool for several minutes; measure and record its mass.
9.
Repeat steps #2-8 for two additional trials, using new water each time. Record the starting
temperature, final temperature, and mass change for each trial.
CP Chemistry
Theodore Roosevelt High School
Lab #3-3
Additional Clean-up and Disposal
1.
Dispose of any weigh paper, paper towels or matches in the trash can.
Data – you should create a data table in your lab write-up that looks something like this:
Trial
Starting
Mass
Starting
Temp
Final
Mass
Final
Temp
ΔH*
q*
Trial #1
Trial #2
Calculations (Include these answers in your Conclusion!)
1.
Calculate the average theoretical heat change for the three trials due to the combustion of paraffin
(in kJ)
[ΔH = -41.5 kJ/g].
2.
Calculate the average heat change (q) of the water (in kJ) for the three trials.
3.
Calculate your percent error in this experiment, using the heat change of water as the
experimental value and the heat change due to combustion of paraffin as the accepted value.
Questions
1.
Why is the heat change for the combustion of paraffin a negative value? Why is the heat change
for the water a positive value?
2.
One of the products of the combustion of paraffin is water. What sort of experiment could you
design to show this is formed?
3.
When a candle burns, is it the wax or the wick that burns? Explain why.
Errors
Describe two possible errors you may have committed in this lab that may have somehow affected your
results. Explain the specific steps you will take to avoid each of these errors in the future.
Conclusion
Write two or more paragraphs summarizing your results, examining the validity of your prediction, and
explaining your calculations.
CP Chemistry
Theodore Roosevelt High School
Heat of Combustion of a Candle Lab workspace:
Lab #3-3
CP Chemistry
Theodore Roosevelt High School
Lab #3-4
Molar Mass of Butane Lab
Introduction
When a new substance is prepared in the laboratory, its identity must be
determined. Knowing the molar mass of the substance limits the list of
possible identities. To determine the molar mass, you need the mass of
the sample and the number of moles of substance present in that
particular mass. Knowing the pressure and volume of a gas at a specific
temperature provides enough information to determine the number of
moles present. One method of determining the volume of a gas sample at a known pressure is to
collect it over water. If the volume (V), temperature (T) and total pressure (P) of the collected gas are
measured, the ideal gas law can be used to determine the moles of gas in that sample.
Butane is a gas at normal room conditions, but it is a liquid in disposable lighters under highpressurized conditions. When the lighter is opened, the container is depressurized, allowing the butane
to escape as a gas. In this experiment you will collect a butane gas sample in a container by the water
displacement method, allowing direct measurement of the volume of butane gas collected.
Purpose
Based on the introduction above, determine the purpose of this lab and include it in your lab write-up.
Prediction
Do you think 100 mL of butane gas is enough to accurately determine the molar mass of butane? Why
or why not?
Materials
butane lighter [C4H10]
tap water
Equipment
electronic balance, 0.001 g
gas pressure sensor
graduated cylinder, 100 mL
plastic trough or dishpan
thermometer
Vernier LabQuest
Safety Considerations
• Butane is toxic and highly flammable. No open flames should be used in this experiment!
• Sometimes chemicals from previous labs still remain in glassware and on other lab equipment;
wash all lab equipment before and after performing this lab.
• Wash your hands thoroughly after completing this lab.
Procedure
1.
Place the lighter under water. Remove the lighter, shake off
the excess water, and dry the outside with a paper towel.
Using the balance, determine the mass of the lighter and
record.
2.
Fill the plastic trough two-thirds full with water.
3.
Fill a 100-mL graduated cylinder to the brim with water.
Using the palm of your hand, completely cover the opening of
the graduated cylinder and invert it into the trough. Once the
opening is under water, remove your hand, keeping the
opening of the graduated cylinder under water at all times. If
there are any noticeable air bubbles in the graduated cylinder,
you must remove the cylinder and repeat this step.
This diagram shows a similar setup
using an Erlenmeyer flask; you will
use a graduated cylinder instead.
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4.
5.
6.
7.
8.
9.
Theodore Roosevelt High School
Lab #3-4
Hold the lighter under the opening of the graduated cylinder and release the butane gas by
depressing the lever. Collect exactly 95.0 mL of butane gas. Do not to allow any bubbles of
butane to escape outside the cylinder. Do not exceed 95.0 mL since this may prevent you from
making an accurate volume measurement.
Determine the temperature of the water in °C and record.
Carefully raise or lower the graduated cylinder until the water level inside the cylinder is the same
as the water level in the trough. Be careful not to pull the cylinder out of the water! While
maintaining equal water levels, read the exact volume of the butane gas to the nearest 0.1 mL
and record.
While keeping it upside down, remove the graduated cylinder and take it to the fume hood to
release the collected butane gas safely.
Remove the lighter from the water, shake off the excess water, and dry the outside with a paper
towel. Determine the mass the lighter and record.
Record the barometric pressure from the Vernier LabQuest.
Additional Clean-up and Disposal
1.
Return all used equipment and materials to the supplies table; return the lighter to your teacher.
Data – you should create a data table in your lab write-up that looks something like this:
Property
Value
mass of lighter before
mass of lighter after
water temperature
Water Vapor Pressure Table
T (°C)
0
1
2
3
4
5
6
7
8
9
10
11
P (kPa)
0.61
0.66
0.71
0.76
0.81
0.87
0.93
1.00
1.07
1.15
1.23
1.31
T (°C)
12
13
14
15
16
17
18
19
20
21
22
23
P (kPa)
1.40
1.50
1.60
1.70
1.82
1.94
2.06
2.20
2.34
2.49
2.64
2.81
T (°C)
24
25
26
27
28
29
30
31
32
33
34
35
P (kPa)
2.98
3.17
3.36
3.56
3.78
4.00
4.24
4.49
4.75
5.03
5.32
5.62
T (°C)
36
37
38
39
40
50
60
70
80
90
100
P (kPa)
5.94
6.27
6.62
6.99
7.37
12.3
19.9
31.2
47.3
70.1
101.3
Calculations (Include these answers in your Conclusion!)
1.
Determine the pressure of the butane gas by subtracting the water vapor pressure of the system
from the atmospheric pressure.
2.
Convert the volume of butane gas you collected from milliliters into Liters.
CP Chemistry
3.
4.
5.
6.
Theodore Roosevelt High School
Lab #3-4
Convert the temperature of the system into Kelvins.
Using the ideal gas constant (R) and the pressure, volume, and temperature of the butane gas in
your experiment, determine the number of moles (n) of butane gas you collected.
Determine the molar mass of butane by dividing the mass of gas released from the lighter by the
number of moles (n) of you determined in Calculation #4.
Calculate the percent error for your experimental value of the molar mass of butane.
Questions
1.
Explain how butane, which can be stored as a liquid in lighters, comes out as a gas.
2.
Butane gas does not dissolve well in water. Why is this critical to performing this experiment?
3.
The diagram on the first page shows this experiment being performed with an Erlenmeyer flask
instead of a graduated cylinder.
a.
Why is it preferable to use a graduated cylinder instead of a flask in this lab?
b.
Imagine you performed this lab and collected the gas with a flask instead of a graduated
cylinder. How might you attempt to accurately determine its volume?
Errors
Describe two possible errors you may have committed in this lab that may have somehow affected your
results. Explain the specific steps you will take to avoid each of these errors in the future.
Conclusion
Write two or more paragraphs summarizing your results, examining the validity of your prediction, and
explaining your calculations.
CP Chemistry
Theodore Roosevelt High School
Molar Mass of Butane Lab workspace:
Lab #3-4
CP Chemistry
Theodore Roosevelt High School
Lab #3-5
Ideal Gas Constant Lab
Introduction
The ideal gas law is represented by the equation PV = nRT, where R is the ideal gas constant. In this
lab, you will attempt to experimentally determine the value of R. To do this, you must determine the
values of P, V, n and T by generating and collecting a sample of hydrogen gas from the reaction
between magnesium and hydrochloric acid in an upside-down graduated cylinder. The hydrochloric
acid will be in excess and the magnesium ribbon will be wrapped in a copper wire ‘cage’ to ensure that
the magnesium ribbon reacts completely and produces the proper amount of hydrogen gas.
Purpose
Based on the introduction above, determine the purpose of this lab and include it in your lab write-up.
Prediction
Do you expect that the atmospheric pressure in the lab will be above or below standard atmospheric
pressure (101.3 kPa)? Explain.
Materials
copper wire [Cu]
hydrochloric acid, 3.0 M [HCl]
magnesium ribbon [Mg]
Equipment
beaker, 400 mL
gas pressure sensor
graduated cylinder, 10 mL
latex gloves
pipette
rubber stopper, one-hole
ruler
thermometer
Safety Considerations
• 3M hydrochloric acid is dangerously caustic! Avoid contact with the
skin and eyes.
• Safety goggles must be worn at all times; gloves must be worn in
Steps #5-8.
• Sometimes chemicals from previous labs still remain in glassware and
on other lab equipment; wash all lab equipment before and after
performing this lab.
• Wash your hands thoroughly after completing this lab.
Procedure
1.
Using a ruler, measure and record the exact length of a small
piece of magnesium ribbon. The length of the ribbon piece
should be between 0.6 and 0.8 cm.
2.
Wrap the copper wire around the magnesium ribbon,
making a ‘cage’ that surrounds the ribbon as shown in the
first figure to the right. Leave a handle of copper wire
approximately 6 cm long.
3.
Insert the handle end of the copper wire into the one-hole
rubber stopper as shown in the second figure to the right.
4.
Fill the 400 mL beaker approximately half full with tap water.
5.
While wearing latex gloves, use a pipette to add
approximately 3 mL of 3.0 M hydrochloric acid to the
graduated cylinder.
6.
Using the pipette, gently fill the graduated cylinder by
drizzling water down the inside wall of the cylinder to avoid
CP Chemistry
7.
8.
9.
10.
11.
12.
13.
Theodore Roosevelt High School
Lab #3-5
mixing with the acid. Since HCl is more dense than water, it will stay at the bottom of the cylinder.
Gently insert the stopper into the graduated cylinder while keeping the copper wire cage at the top
of the cylinder.
While holding your finger over the hole in the rubber stopper, quickly but carefully turn the
graduated cylinder upside down and place it into the beaker of water as shown in the third figure
to the right. Once the top of the cylinder is underwater, remove your finger and rest the cylinder in
the beaker while the reaction proceeds.
When the magnesium ribbon is no longer reacting, tap the side of the cylinder to release any
trapped gas bubbles.
Let the cylinder sit for 5 minutes so that the temperature of the system returns to room
temperature. Measure and record the temperature of the water in the beaker.
Using the gas pressure sensor, measure and record the atmospheric pressure in the lab.
Lift the graduated cylinder slightly until the levels of water inside and outside the cylinder are the
same. Measure and record the volume of gas in the cylinder.
Remove the cylinder from the beaker, remove the stopper from the cylinder, and dispose of the
liquid in both containers in the sink. Clean all lab equipment used and return each item to its
proper place.
Additional Clean-up and Disposal
1.
Empty the solids from your waste beaker in the trash and dump the tap water in the sink.
Data – you should create a data table in your lab write-up that looks something like this:
Property
Value
length of Mg ribbon
water temperature
Water Vapor Pressure Table
T (°C)
0
1
2
3
4
5
6
7
8
9
10
11
P (kPa)
0.61
0.66
0.71
0.76
0.81
0.87
0.93
1.00
1.07
1.15
1.23
1.31
T (°C)
12
13
14
15
16
17
18
19
20
21
22
23
P (kPa)
1.40
1.50
1.60
1.70
1.82
1.94
2.06
2.20
2.34
2.49
2.64
2.81
T (°C)
24
25
26
27
28
29
30
31
32
33
34
35
P (kPa)
2.98
3.17
3.36
3.56
3.78
4.00
4.24
4.49
4.75
5.03
5.32
5.62
T (°C)
36
37
38
39
40
50
60
70
80
90
100
P (kPa)
5.94
6.27
6.62
6.99
7.37
12.3
19.9
31.2
47.3
70.1
101.3
Calculations (Include these answers in your Conclusion!)
1.
Knowing that 100.0 cm of magnesium ribbon has a mass of 1.06 g, calculate the number of
moles of magnesium that were reacted (hint: convert your recorded length to grams, then to
CP Chemistry
2.
3.
4.
5.
6.
7.
Theodore Roosevelt High School
Lab #3-5
moles).
Using the balanced equation for the reaction between magnesium and hydrochloric acid,
determine the number of moles of hydrogen gas that were produced.
Determine the pressure of the hydrogen gas by subtracting the water vapor pressure of the
system from the atmospheric pressure.
Convert the volume of hydrogen gas produced from milliliters into Liters.
Convert the temperature of the system into Kelvins.
Using the pressure, volume, temperature and moles of hydrogen gas in this system, calculate
your experimental value of the ideal gas constant, R.
Using the accepted value for the ideal gas constant, R, determine the percent error for your
experimental value of the ideal gas constant.
Questions
1.
Using your experimental value of R, determine the molar volume of a gas at STP (solve for n if V
= 1 L). How does this compare to the accepted value, 22.4 L/mol?
2.
Describe three observations from your lab that showed a chemical reaction took place.
3.
When exposed to hydrochloric acid, the copper wire reacted very differently than the magnesium
ribbon. What chemical explanation can you give for why this occurred?
Errors
Describe two possible errors you may have committed in this lab that may have somehow affected your
results. Explain the specific steps you will take to avoid each of these errors in the future.
Conclusion
Write two or more paragraphs summarizing your results, examining the validity of your prediction, and
explaining your calculations.
CP Chemistry
Theodore Roosevelt High School
Ideal Gas Constant Lab workspace:
Lab #3-5
CP Chemistry
Theodore Roosevelt High School
Lab #3-6
Half-Life of a Penny Lab
Introduction
One characteristic of radioactive material is that radioactive isotopes
spontaneously give off particles. This process, called radioactive decay, changes
the nucleus of the material. The length of time it takes for half of a sample of
radioactive material to decay is called the half-life. Each radioactive isotope has
a characteristic half-life, ranging from less than a second to millions of years. In
this activity, you will use pennies that can land heads, to represent nuclei that
have undergone radioactive decay, or tails, to represent those who haven’t. as a
simplified model of how half-life is determined.
Purpose
Based on the introduction above, determine the purpose of this lab and include it in your lab write-up.
Prediction
On average, what percentage (%) of pennies should show ‘heads up’ for each shake of the shoe box?
Why do you think so?
Materials
pennies, 100
Equipment
shoe box or other cardboard box
Safety Considerations
• None for this lab beyond standard lab safety procedures.
Procedure
1.
Count out 100 pennies and place all of them ‘tails up’ into the shoe box. Close the box.
2.
While securely holding the lid closed, shake the box for several seconds.
3.
Open the box and remove all of the pennies that are ‘heads up’.
4.
Count the number of pennies remaining in the box and record. DO NOT PUT ANY PENNIES
BACK IN THE BOX!
5.
Close the box and repeat Steps #2-4 until only one penny remains or the box is empty.
6.
Perform two additional trials by repeating Steps #1-5.
Calculations (Include these answers in your Conclusion!)
1.
Using the data you collected in this lab, construct a line graph showing the relationship between
trials and number of pennies. You may combine all three trials in one graph, or construct one
graph per trial. Label your axes and title your graph(s) appropriately.
2.
Select one of your three trials and determine the average percentage of pennies that were
removed with each shake. How close is this value to 50%?
Questions
1.
In this lab, what did the pennies represent? What did one trial represent?
2.
In your graph, which variable went on the x-axis? Which variable went on the y-axis? Explain
why for both.
3.
Theoretically, 50% of the pennies should ‘decay’ with each shake. Did this actually happen?
Explain why or why not.
CP Chemistry
Theodore Roosevelt High School
Lab #3-6
Errors
Describe two possible errors you may have committed in this lab that may have somehow affected your
results. Explain the specific steps you will take to avoid each of these errors in the future.
Conclusion
Write two or more paragraphs summarizing your results, examining the validity of your prediction, and
explaining your calculations.
CP Chemistry
Theodore Roosevelt High School
Half-Life of a Penny Lab workspace:
Lab #3-6
CP Chemistry
Theodore Roosevelt High School
Lab #3-7
Energy Content of Foods – Capstone Lab
Introduction
You are to assume the role of a lab technician working for NASA. Recently, you
were given the job of deciding what type of foods should be included in the next
space mission. Seven food types have been selected as possible snacks for the
astronauts. You must determine which of these seven food choices has the highest
energy content, while adding the least amount of mass to the mission.
Your team will test all four food types using a method known as calorimetry. During
this process, you will burn a food sample positioned below a test tube containing a
known amount of cold water. By calculating the temperature change of the water,
you will determine how much energy was released when the food sample burned.
Purpose
To determine how much chemical energy is stored in several different food samples.
Equipment
Determine all equipment you will use and list it in your lab write-up.
Materials
Determine all materials you will use and list them in your lab write-up.
Safety Considerations
• Sometimes chemicals from previous labs still remain in glassware and on other lab equipment;
wash all lab equipment before and after performing this lab.
• Wash your hands thoroughly after completing this lab.
Procedure
As you perform the lab, record your procedure steps, and then describe them in your lab write-up.
Additional Clean-up and Disposal
1.
Empty the solids from your waste beaker in the trash and dump the tap water in the sink.
Data
Record all pertinent data and include it in your lab write-up.
Calculations (Include the answers in your Conclusion!)
1.
Use the same procedure in the Heat of Combustion of a Candle Lab to:
• calculate the average heat change (q) of the water (in kJ) for each burned food sample.
• calculate the energy content of each food sample by dividing its calculated heat change by its
mass.
Errors
Describe two possible errors you may have committed in this lab that may have somehow affected your
CP Chemistry
Theodore Roosevelt High School
Lab #3-7
results. Explain the specific steps you will take to avoid each of these errors in the future.
Conclusion
Write two or more paragraphs summarizing and explaining your results, as well as critically analyzing
your procedure methods.
CP Chemistry
Theodore Roosevelt High School
Energy Content of Foods Capstone Lab workspace:
Lab #3-7
th
4 Quarter
Laboratory Activities
CP Chemistry
Theodore Roosevelt High School
Lab #4-0
Properties of Water: Stations Lab
Introduction
Water has several unusual properties that sets it apart as one of the most unique
substances on Earth, and certainly one of the most important! The hydrogen
bonding that occurs between molecules results in much higher melting points and
boiling points as well as a much lower vapor pressure; this allows water to exist at
temperatures that make life on our planet possible. In this lab, we will use a variety
of common household items and substances to look into some of the more peculiar
aspects of this important chemical.
Purpose
To observe the properties of water in various situations.
Materials
beaker, 250-mL
corn syrup
dish detergent
isopropyl alcohol,
green
Kool-Aid solution
laundry detergent,
powdered
salt [NaCl]
sugar [C12H22O11]
vegetable oil
water, distilled
water, tap
Equipment
conductivity meter
graduated cylinder,
100-mL
paper clip, small
paper cup
penny
Petri dish
pipette
plastic spoon, plain
plastic spoon w/
Magic Sand
rubber band
stirring rod
well plate
Safety Considerations
• Sometimes chemicals from previous labs still remain in glassware and on other lab equipment;
wash all lab equipment before and after performing this lab.
• Wash your hands thoroughly after completing this lab.
Procedure
For each of the following stations, follow the directions and record your observations in the data
table. You may complete the stations in any order.
Station A – “Drowning Lincoln”
1.
Obtain a penny, a pipette, and a beaker with 200-mL of tap water.
2.
Using the pipette, count the number of drops of tap water you can place on the head of your
penny before the water spills over the side. Record this number in a data table.
3.
Perform two additional trials by repeating step #A2 twice.
4.
Add approximately ½ teaspoon of powdered laundry detergent to the beaker of tap water. Mix the
detergent in the water until it dissolves thoroughly.
5.
Repeat step #A2 using the detergent solution. Record this number in the data table.
6.
Perform two additional trials by repeating step #A5 twice.
7.
Discard the pipette in the trash; return the penny to the supplies table.
Station B – Floating a Paper Clip
1.
Obtain a paper cup and a small paper clip.
2.
Fill the paper cup to the edge with tap water.
3.
Carefully slide the paper clip onto the surface of the water. Record your observations in a data
table.
4.
Remove the paper clip and add approximately ½ teaspoon of salt to the water in the paper cup.
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5.
6.
Theodore Roosevelt High School
Lab #4-0
Repeat step #B3 using the salt solution. Record your observations in the data table.
Discard the paper cup in the trash; return the paper clip to the supplies table.
Station C – Dispersion of Oil
1.
Obtain a Petri dish, a rubber band, a small amount of vegetable oil, and liquid dish detergent.
2.
Thoroughly clean and dry the Petri dish.
3.
Fill the Petri dish almost all the way full of water.
4.
Carefully place the rubber band on the surface of the water.
5.
Slowly add oil dropwise to the water inside the rubber band until it is covered by a layer of oil.
Record your observations.
6.
Add one drop of liquid dish detergent to the center of the oil layer. Record your observations.
7.
Remove the rubber band from the Petri dish; pour the contents of the Petri dish down the sink;
wash the Petri dish; return the rubber band, Petri dish, vegetable oil and liquid dish detergent to
the supplies table.
Station D – Layers of Liquids
1.
Obtain corn syrup, green isopropyl (rubbing) alcohol, Kool-Aid, vegetable oil and a 100-mL
graduated cylinder.
2.
Pour 10-mL of corn syrup into the graduated cylinder.
3.
Slowly add 10-mL of Kool-Aid to the graduated cylinder by pouring it down the side of the
graduated cylinder.
4.
Slowly add 10-mL of vegetable oil to the graduated cylinder by tipping it slightly and pouring it
down the side.
5.
Very carefully add 10-mL of green rubbing alcohol on top of the oil in the graduated cylinder.
Record your observations.
6.
Cover the mouth of the graduated cylinder completely with the palm of your hand and carefully
shake it up and down. Allow the cylinder to sit for at least one minute. Record your observations.
7.
Pour the contents of the graduated cylinder down the sink; wash the graduated cylinder with dish
soap using a test tube brush; return the corn syrup, rubbing alcohol, Kool-Aid and vegetable oil to
the supplies table.
Station E – “Magic” Spoon
1.
Obtain a plain plastic spoon, a Magic Sand plastic spoon, a pipette and a beaker with 50-mL of
tap water.
2.
Using the pipette, add a small amount of tap water to the plain plastic spoon.
3.
Try to roll the water around in the spoon. Record your observations.
4.
Repeat steps #E2-E3 with the Magic Sand plastic spoon. Record your observations.
5.
Discard the pipette in the trash; return the spoons to the supplies table.
Station F – Electrolyte Conductivity
1.
Obtain a pipette, a well plate, a conductivity meter, a small amount of sucrose, a small amount of
salt and a beaker with 10-mL of distilled water.
2.
Using the pipette, add approximately 10 drops of distilled water to three wells of the well plate.
3.
Add a small amount of sucrose to the second well; add a small amount of salt to the third well; do
not add anything to the first well.
4.
Turn on and place the conductivity meter in the first well. Use the scale on the back of the meter
to determine the conductivity. Record the conductivity in a data table.
5.
Remove the conductivity meter from the well and rinse it off in the sink. Dry the probes
completely and repeat steps #F4-F5 for the second and third wells. Be careful not to crosscontaminate your wells! Record the conductivity in the data table.
6.
Discard the pipette and excess salt and sucrose in the trash; pour the contents of the well plate
down the sink and rinse it thoroughly; return the conductivity meter to the supplies table.
CP Chemistry
Theodore Roosevelt High School
Lab #4-0
Data – record your data in the table below:
Station
Observations
Station A
Station B
Station C
Station D
Station E
Station F
Station G
Station H
Questions for discussion
1.
Detergent is a well-known surfactant. Did its presence have an effect on the number of drops of
water that would fit on a penny? Why or why not?
2.
What property of water allowed the paper clip to be placed on its surface? Was this property
affected by the presence of dissolved salt?
3.
Which solution had the best conductivity? Why do you think this was the case?
Errors
Think of two possible errors you may have committed in this lab that may have somehow affected your
results and record them below. Explain the specific steps you will take to avoid each of these errors in
the future.
1.
2.
Conclusion
Describe what you learned while doing this lab:
CP Chemistry
Theodore Roosevelt High School
Lab #4-1
Dilution of Solutions Lab
Introduction
All human activity and many natural processes produce pollution. Pollution is a
generic term for contamination from any activity that has a negative impact on the
environment or human health. Pollution can travel by three major pathways: air, water,
and land. Since it can travel using several different methods, it can be very difficult to
remove pollution completely once an area has been contaminated. Sometimes even
very small amounts of pollution can have a negative effect on people, animals and
plants, so detecting and removing it can be complicated and expensive.
In this lab, we will take a sample of a chemical and treat it as if it is ‘polluted water’. We will then dilute
the sample five times, decreasing its concentration by ten times for each step, all the way down to onehundred thousandth of the original concentration. Finally, we’ll test each sample with a drop of
chemical indicator to attempt to detect ‘pollution’ at each concentration.
Purpose
Based on the introduction above, determine the purpose of this lab and include it in your lab write-up.
Prediction
Do you that you will be able to dilute the samples in this lab to levels that are no longer detectable?
Materials
distilled water
iron (III) chloride [FeCl3], 0.1M
phenolphthalein indicator solution, 1%
potassium thiocyanate solution [KSCN], 0.1M
silver nitrate solution [AgNO3], 0.1M
sodium chloride [NaCl], 0.1M
sodium hydroxide [NaOH], 0.1M
Equipment
graduated cylinder, 10-mL
medium test tubes, 6
plastic pipettes, 3
test tube rack
Safety Considerations
• Silver nitrate and potassium thiocyanate are toxic; sodium hydroxide is caustic! Avoid contact
with the skin and eyes.
• Safety goggles must be worn at all times; gloves are optional but highly recommended.
• Silver nitrate can stain light-colored clothing; you may want to wear a lab apron during this lab.
• Sometimes chemicals from previous labs still remain in glassware and on other lab equipment;
wash all lab equipment before and after performing this lab.
• Wash your hands thoroughly after completing this lab.
Procedure
1.
Obtain six medium test tubes and a test tube rack. Place the test tubes in the test tube rack.
2.
Obtain one of the three solutions representing ‘polluted water’: NaOH, FeCl3, or NaCl. Note its
color in your observations.
3.
Using a small graduated cylinder, measure out exactly 10 mL of ‘polluted water’.
4.
Pour the 10 mL of ‘polluted water’ into the first test tube on the left. Rinse out the graduated
cylinder thoroughly.
5.
Return the original sample of ‘polluted water’ to the supplies table.
CP Chemistry
6.
7.
8.
9.
10.
Theodore Roosevelt High School
Using a plastic pipette, remove enough ‘polluted water’ from the first test tube to make 1 mL in the
graduated cylinder.
Pour the 1 mL of ‘polluted water’ in the second test tube. Rinse out the graduated cylinder.
Using the small graduated cylinder, measure out exactly 9 mL of distilled water.
Pour the 9 mL of distilled water into the second test tube. This dilutes the polluted sample to a
concentration ten times less than the original.
Repeat Steps 6-9 for each test tube, each time using the previous test tube to obtain your 1 mL
sample until all six test tubes have ‘polluted water’ samples like this:
original
(more
sample concentrated)
11.
12.
13.
14.
15.
Lab #4-1
less
concentrated
(more
diluted)
Obtain a sample of ‘indicator’:
• for NaOH, use phenolphthalein
• for FeCl3, use KSCN
• for NaCl, use AgNO3
Add two drops of ‘indicator’ to each test tube. Gently wiggle or swirl the test tube to allow the
reaction to mix fully. Observe any color changes and record your observations in a data table;
you may want to hold a piece of white paper behind the test tubes in order to make the color
differences appear more distinct.
Compare your known test tube concentrations to the appropriate unknown sample as described in
Procedure B below.
Dispose of the AgNO3 solution only in the heavy metals waste container; the other solutions can
go down the sink. Wash your test tubes thoroughly with soap using a test tube brush.
Repeat steps #2-13 of this procedure for the other two samples of ‘polluted water’.
Procedure B – determination of unknowns
1.
Once you have prepared your “known” standard solutions, obtain three test tubes of unknown
solutions from your teacher.
2.
Add two drops of the appropriate ‘indicator’ (see Step #11 above) to each test tube and compare
them to your standards to determine their concentration.
3.
Record your predicted concentration for each test tube in your lab notebook.
4.
Obtain the actual concentration for each test tube from your teacher and record it in your lab
notebook.
5.
Dispose of the solutions properly as described in Procedure A.
Additional Clean-up and Disposal
1.
Dispose of the AgNO3 solution only in the heavy metals waste container; the other solutions can
go down the sink.
2.
Wash your test tubes thoroughly with soap using a test tube brush.
CP Chemistry
Theodore Roosevelt High School
Lab #4-1
Data – you should create three data tables in your lab write-up that look something like this:
Test Tube #
Concentration
1
0.1 M NaOH
(original)
2
0.01 M NaOH
Observations
Calculations (Include these answers in your Conclusion!)
1.
Determine the concentration of each solution in each test tube and record it in your data table.
2.
Knowing that there are 6.02 x 1023 formula units per mole of any chemical, determine how many
formula units of each chemical you tested are in the sixth, least concentrated test tube.
Questions
1.
What trend did you notice in the colors of the chemical reaction as your solutions became less
concentrated or more dilute? Why do you think this happened?
2.
What specific steps would you take to dilute one of these solutions down to one-billionth of its
original concentration?
3.
Do you think it would be possible to remove pollution from a water source by simply diluting it?
Why or why not?
Errors
Describe two possible errors you may have committed in this lab that may have somehow affected your
results. Explain the specific steps you will take to avoid each of these errors in the future.
Conclusion
Write two or more paragraphs summarizing your results, examining the validity of your prediction, and
explaining your calculations.
CP Chemistry
Theodore Roosevelt High School
Dilution of Solutions Lab workspace:
Lab #4-1
CP Chemistry
Theodore Roosevelt High School
Lab #4-2
Supersaturation Lab
Introduction
Under certain conditions, a solution may contain more solute than is
normally contained in a saturated solution at the same temperature. This
type of solution is unstable and is called ‘supersaturated’. The solubility of
most substances decreases as temperature decreases. As a solution
cools, any excess solute may or may not crystallize out. If the excess
solute remains in solution, that solution becomes supersaturated.
Purpose
Based on the introduction above, determine the purpose of this lab and include it in your lab write-up.
Prediction
What do you think will happen when you add more solute to the supersaturated solution?
Materials
distilled water
ice
sodium sulfate decahydrate [Na2SO4·10H2O]
Equipment
beaker, 100 mL
Bunsen burner
electronic balance
graduated cylinder, 10 mL
test tube holder
test tube, medium
test tube rack
Safety Considerations
• When heating a test tube, never point the mouth of the tube at yourself or anyone else!
• Safety goggles must be worn at all times.
• Sometimes chemicals from previous labs still remain in glassware and on other lab equipment;
wash all lab equipment before and after performing this lab.
• Wash your hands thoroughly after completing this lab.
Procedure
1.
Place 5.0 g of Na2SO4·10H2O in a clean medium-sized test tube. Add 10 mL of distilled water.
2.
Hold the test tube in a test-tube holder and heat it in a burner flame, agitating the mixture gently
until all of the solid has dissolved. Place the test tube in a test-tube rack. Add one more crystal of
Na2SO4·10H2O to the warmed solution and gently agitate it. Record your observations.
3.
Place the test tube in a beaker of ice water to cool. Be careful not to disturb the test tube during
the cooling process. If crystals begin to form as the tube is cooling, gently reheat the tube to redissolve the crystals; cool the tube again.
4.
When the solution is cold, gently remove the tube from the ice water bath and put it in the testtube rack. Add one small crystal of Na2SO4·10H2O. Touch the bottom of the test tube to the palm
of your hand. Record your observations.
Additional Clean-up and Disposal
1.
Once the change has finished, dispose of the contents of the test tube in the waste beaker.
2.
Using a test tube brush, clean the test tube with soap and water.
CP Chemistry
Theodore Roosevelt High School
Lab #4-2
Questions
1.
Why is it necessary to heat the mixture in step #2 of the procedure?
2.
How could you test whether a solution is unsaturated, saturated or supersaturated? Explain how
interpret the results.
3.
Based on the results of this lab, what hypothesis could you develop relating the effect of the rate
of cooling to the stability of a supersaturated solution?
Errors
Describe two possible errors you may have committed in this lab that may have somehow affected your
results. Explain the specific steps you will take to avoid each of these errors in the future.
Conclusion
Write two or more paragraphs summarizing your results, examining the validity of your prediction, and
explaining your calculations.
CP Chemistry
Theodore Roosevelt High School
Supersaturation Lab workspace:
Lab #4-2
CP Chemistry
Theodore Roosevelt High School
Lab #4-3
Natural Indicators Lab
Introduction
Red cabbage (Brassica oleracea) has dark reddish-purple leaves due to a
pigment called anthocyanin. This water-soluble pigment is also found in apple
skin, plums, poppies, cornflowers, and grapes. Because of the way this pigment
reacts to chemicals in the environment, the plant itself changes its color
according to the pH value of the soil. This explains the fact that the very same plant is known by
different colors in various regions throughout the world, such as Northern Europe, Northern America
and China.
In this lab, we will determine the pH of several common household chemicals using both universal
indicator and a natural indicator extracted from red cabbage leaves. We will then use the pHs of these
chemicals to compare the colors produced by universal indicator with the colors produced by red
cabbage indicator in order to determine its effective range.
Purpose
Based on the introduction above, determine the purpose of this lab and include it in your lab write-up.
Prediction
Which of the household chemicals do you think will be the most acidic? Basic?
Materials
distilled water
red cabbage
universal indicator
various household chemicals
Equipment
beaker, 250 mL
beaker tongs
Bunsen burner
Erlenmeyer flask, 125 mL
iron rings, 2
pipettes
ring stand
stirring rod
well plate
wire gauze
Safety Considerations
• Be careful not to place bleach and ammonia in adjacent wells – this can generate
poisonous chlorine gas!
• Although you will not have to wear safety goggles, some of the household chemicals are irritating
to the eyes and skin.
• Sometimes chemicals from previous labs still remain in glassware and on other lab equipment;
wash all lab equipment before and after performing this lab.
• Wash your hands thoroughly after completing this lab.
Procedure A – Preparation of Natural Indicator
1.
Obtain one leaf of red cabbage and tear it into small pieces. Place the pieces into a beaker with
150 mL of distilled water.
2.
Using a ring stand, place the beaker on an iron ring with wire gauze above a Bunsen burner. Be
sure to double-ring your beaker!
3.
Heat the water until it has turned a deep purple color, stirring it regularly.
4.
Turn off the Bunsen burner and remove the beaker from the iron ring. Allow the natural indicator
solution to cool for several minutes.
5.
Strain the natural indicator solution by pouring it into an Erlenmeyer flask while holding back the
cooked pieces of cabbage with your stirring rod.
CP Chemistry
Theodore Roosevelt High School
Lab #4-3
Procedure B – Comparison of Indicators
1.
Using a well plate, obtain twelve (12) samples of household chemicals, one in each well. Record
the names of these chemicals in a data table.
2.
Carefully add one drop of universal indicator to each household chemical. Record the color that is
formed and its corresponding pH in your data table.
3.
Clean the well plate carefully in the sink using soap and water.
4.
Repeat Step B1, using the same household chemicals.
5.
Repeat Step B2, this time substituting your natural red cabbage indicator for the universal
indicator. You may need to use several drops before you see a color change. Record the color
that is produced in your data table.
Additional Clean-up and Disposal
1.
Discard the cabbage in the trash; dispose of the extra indicator in the sink. DO NOT LEAVE ANY
CABBAGE PIECES IN THE SINK.
2.
All chemicals, including the natural indicator, can be disposed of in the sink.
Data – you should create a data table in your lab write-up that looks something like this:
Well #
Household
Chemical
Universal Indicator
Color
pH
Red Cabbage Indicator
Color
1
2
Questions
1.
Using your data table, determine the pH range for each color of the red cabbage indicator.
2.
As an acid-base indicator, do you think red cabbage indicator is more effective, less effective, or
about as effective as universal indicator? Why?
3.
What effect did bleach and/or Oxi-Clean have on the red cabbage indicator? Why do you think
this happened?
Errors
Describe two possible errors you may have committed in this lab that may have somehow affected your
results. Explain the specific steps you will take to avoid each of these errors in the future.
Conclusion
Write two or more paragraphs summarizing your results, examining the validity of your prediction, and
explaining your calculations.
CP Chemistry
Theodore Roosevelt High School
Natural Indicators Lab workspace:
Lab #4-3
CP Chemistry
Theodore Roosevelt High School
Lab #4-4
Acid-Base Titration Lab
Introduction
One common task that chemists must perform is to determine the
concentration of a chemical using titration. There are a variety of reasons that
this may be necessary, ranging from finding an unlabeled container in the
stock room to applying forensic techniques in order to identify a sample at a
crime scene. In this experiment you will titrate a measured volume of HCl with
a solution of NaOH of known concentration. The acid and the base react with
one another according to the equation:
HCl (aq) + NaOH (aq) → NaCl (aq) + H2O (l)
During the first stages of the titration, the NaOH will be completely neutralized, and an excess of acid
will remain. However, at the theoretical endpoint, the acid and the base will have neutralized one
another exactly, and the phenolphthalein indicator will turn pink when the acid is completely neutralized
and a slight excess of base is present. In this titration, a successful endpoint is achieved if one drop of
base turns the solution in the flask from colorless to a very faint pink, and at this point, the number of
moles of NaOH used will be equal to the number of moles of HCl in the unknown solution.
Purpose
Based on the introduction above, determine the purpose of this lab and include it in your lab write-up.
Materials
sodium hydroxide solution [NaOH], 0.1M
hydrochloric acid [HCl], unknown
phenolphthalein indicator
Equipment
beakers, 250 mL
buret, 25 or 50 mL
buret clamp
Erlenmeyer flask, 250 mL
ring stand
Safety Considerations
• Hydrochloric acid and sodium hydroxide are caustic! Avoid contact with the skin and eyes.
• Safety goggles must be worn at all times; gloves are optional but highly recommended.
• Sometimes chemicals from previous labs still remain in glassware and on other lab equipment;
wash all lab equipment before and after performing this lab.
• Wash your hands thoroughly after completing this lab.
Procedure
1.
Obtain approximately 120 mL of NaOH in a 250 mL beaker.
2.
Rinse the buret with approximately 10 mL of the NaOH solution, and let the liquid drain through
the buret tip into an empty 250 mL "waste" beaker. Repeat this procedure twice more, using new
10 mL samples of NaOH solution each time.
3.
Refill the buret so that the meniscus of the solution is above the 0 mL mark. Position the buret in
a double buret clamp on a ring stand. Let some of the solution run rapidly from the buret to expel
all air bubbles from the tip and to bring the level of the solution down to the calibrated region of
the buret. If there is a drop of solution hanging on the tip of the buret, remove it by touching the
drop to the inside wall of the 250 mL beaker.
4.
Read the initial volume of the NaOH solution at the bottom of the meniscus. Your eye must be at
the same level as the meniscus.
5.
Pour 20.0 mL of HCl into a clean 250 mL Erlenmeyer flask. Add two drops of phenolphthalein
indicator.
CP Chemistry
6.
7.
8.
Theodore Roosevelt High School
Lab #4-4
Place the Erlenmeyer flask under the tip of the base buret; a piece of white paper placed under
the flask will make it easier to see the color changes. While continuously swirling the flask to
ensure thorough mixing, run in the NaOH solution from the buret. Initially, a pink color will appear
at the point where the NaOH comes in contact with the solution in the flask, but this color
disappears quickly. As the endpoint nears, the color will disappear more slowly. Eventually, the
NaOH should be added drop by drop until one drop turns the entire solution in the flask pink. This
pink color should remain for at least 15 seconds while the solution is being swirled.
If you overshoot the endpoint, you will have to discard the solution and begin again. When you
have reached a satisfactory endpoint, read the final volume of the buret and record the volume of
NaOH used in your data table.
Refill the buret and repeat steps #3-7 twice more, using a clean Erlenmeyer flask.
Additional Clean-up and Disposal
1.
Drain your buret into the waste beaker and rinse it with tap water.
2.
Wash any remaining solutions and materials down the sink.
Data – you should create a data table in your lab write-up that looks something like this:
Trial
Initial NaOH
Titrated Amount
Total
1
2
Calculations (Include these answers in your Conclusion!)
1.
For each trial, calculate the number of moles of NaOH used.
2.
The number of moles of NaOH used is equal to the number of moles of HCl reacted. Based on
your results in the previous calculation, determine the concentration of HCl for each trial.
3.
Obtain the accepted concentration of HCl from your teacher. Using your average experimental
concentration of HCl, determine your percent error for this lab.
Questions
1.
Why does the pink color, which forms at the point where the NaOH comes into contact with the
solution in the flask, disappear more slowly near the endpoint?
2.
Why is it a good idea to carry out titrations in triplicate?
3.
Would the addition of several milliliters of distilled water to the Erlenmeyer flask during the titration
affect the results of the titration? Explain your answer.
Errors
Describe two possible errors you may have committed in this lab that may have somehow affected your
results. Explain the specific steps you will take to avoid each of these errors in the future.
Conclusion
Write two or more paragraphs summarizing your results, examining the validity of your prediction, and
explaining your calculations.
CP Chemistry
Theodore Roosevelt High School
Acid-Base Titration Lab workspace:
Lab #4-4
CP Chemistry
Theodore Roosevelt High School
Lab #4-5
Testing Antacids Lab
Introduction
You are probably familiar with antacids, which are medicinal products
that are used to neutralize stomach acids. Most antacids contain
carbonates or bicarbonates, which not only neutralize acids, but also
produce carbon dioxide gas. Many antacids are insoluble or only
slightly soluble in water to prevent being absorbed into the
bloodstream. This would produce excess base in the blood, which is
a condition called alkalosis.
In this lab, we will test two brands of antacids to see which can neutralize the most acid. We will use
the familiar titration technique with a new indicator, phenol red, which is a pink-red color when basic
and a yellow color when neutral or acidic.
Purpose
Based on the introduction above, determine the purpose of this lab and include it in your lab write-up.
Prediction
Which antacid brand will be the most effective? Why?
Materials
antacids, various
hydrochloric acid [HCl], 0.01 M
phenol red indicator
Equipment
beakers, 250 mL
buret, 25 or 50 mL
buret clamp
Erlenmeyer flask, 125 mL
mortar & pestle
ring stand
Safety Considerations
• Hydrochloric acid is caustic! Avoid contact with the skin and eyes.
• Safety goggles must be worn at all times; gloves are optional but recommended.
• Sometimes chemicals from previous labs still remain in glassware and on other lab equipment;
wash all lab equipment before and after performing this lab.
• Wash your hands thoroughly after completing this lab.
Procedure
1.
Obtain approximately 100 mL of 0.01M hydrochloric acid solution in a 250 mL beaker.
2.
Rinse the buret with approximately 10 mL of the HCl solution, and let the liquid drain through the
buret tip into an empty 250 mL "waste" beaker. Repeat this procedure twice more, using new
samples of HCl solution each time.
3.
Refill the buret with HCl so that the meniscus of the solution is above the 0 mL mark. Position the
buret in a double buret clamp on a ring stand. Let some of the solution run rapidly from the buret
to expel all air bubbles from the tip and to bring the level of the solution down to the calibrated
region of the buret. If there is a drop of solution hanging on the tip of the buret, remove it by
touching the drop to the inside wall of the 250 mL beaker.
4.
Read the initial volume of the HCl solution at the bottom of the meniscus. Your eye must be at the
same level as the meniscus. Record this initial volume in a data table in your data table.
5.
Obtain an antacid tablet and measure its mass. Record this information, along with the brand
name and active ingredients, in the data table.
6.
Using a clean mortar and pestle, crush the tablet into a fine powder. Pour all of the antacid
CP Chemistry
7.
8.
9.
10.
Theodore Roosevelt High School
Lab #4-5
powder into a clean 125 mL Erlenmeyer flask.
Add 20.0 mL of distilled water to the Erlenmeyer flask. Swirl the flask for thirty seconds to try to
dissolve as much of the antacid as possible. Add four drops of phenol red indicator to the flask.
Place the Erlenmeyer flask under the tip of the base buret. While continuously swirling the flask
to ensure thorough mixing, run in the HCl solution from the buret. As the endpoint nears, the
color will change more slowly. Eventually, the HCl should be added drop by drop until one drop
changes the color of the entire solution in the flask. This new color should remain for at least 15
seconds while the solution is being swirled.
If you overshoot the endpoint, you will have to discard the solution and begin again. When you
have reached a satisfactory endpoint, read the final volume of the buret. Record the final volume
in the data table.
Clean your Erlenmeyer flask and repeat steps #3-9 for two additional brands of antacid tablets.
Additional Clean-up and Disposal
1.
Drain your buret into the waste beaker and rinse it with tap water.
2.
Wash any remaining solutions and materials down the sink.
Data – you should create a data table in your lab write-up that looks something like this:
Antacid
Mass
Initial HCl
Titrated Amount
Total
Tums
Rolaids
Calculations (Include these answers in your Conclusion!)
1.
Using your data, determine which antacid is more effective at neutralizing acid per tablet.
2.
Using your data, determine which antacid is more effective at neutralizing acid per gram.
Questions
1.
What advantage does phenol red have over phenolphthalein in this lab?
2.
Does it matter how much distilled water you add to the antacid powder? Why or why not?
3.
What difference is there between the active ingredients of the antacids? What effect, if any, do
you believe this has on their ability to neutralize acid?
Errors
Describe two possible errors you may have committed in this lab that may have somehow affected your
results. Explain the specific steps you will take to avoid each of these errors in the future.
Conclusion
Write two or more paragraphs summarizing your results, examining the validity of your prediction, and
explaining your calculations.
CP Chemistry
Theodore Roosevelt High School
Testing Antacids Lab workspace:
Lab #4-5
CP Chemistry
Theodore Roosevelt High School
Lab #4-6
Making Artificial Fragrances Lab
Introduction
In order to enhance their appeal, many foods contain artificial
flavorings, while many other consumer products contain artificial
fragrances. The molecules that give these products their distinctive
odors are called ‘esters’. Esters are produced by the reaction of
alcohols with organic acids in the presence of a strong acid such as
sulfuric acid, which works as a catalyst.
The generic reaction between an organic acid and an alcohol is:
RCOOH + HOR’ → RCOOR’ + H2O
where R and R’ represent carbon chains, RCOOH represents an organic acid, HOR’ represents an
alcohol, and RCOOR’ represents an ester. Esters are named by using the alcohol name with the acid
name after its suffix has been changed to ‘-ate’. For example, ethyl alcohol and acetic acid produce
the ester ethyl acetate.
In this lab, you will prepare three types of fragrant ester molecules from their original components. You
will also name these fragrances using your knowledge of organic chemistry.
Purpose
Based on the introduction above, determine the purpose of this lab and include it in your lab write-up.
Prediction
Which fragrance do you think will smell the most like what it is supposed to?
Materials
alcohols:
• n-amyl alcohol (C5H11OH)
• methyl alcohol (CH3OH)
• ethyl alcohol (C2H5OH)
organic acids:
• salicylic acid (C7H6O3)
• butyric acid (C4H8O2)
• glacial acetic acid (CH3COOH)
• sulfuric acid, concentrated (H2SO4)
Equipment
beaker, 400 mL
graduated cylinder, 10 mL
hot plate
small test tubes, 3
Safety Considerations
• Concentrated sulfuric acid is EXTREMELY dangerous! You must wear goggles, gloves and a lab
apron at all times while working with chemicals. Your teacher will dispense the sulfuric acid for
you.
• Glacial acetic acid is also VERY dangerous! Take special care not to inhale its vapors or spill any
on your skin.
• Because some of the fragrances may have acid remaining after they have reacted, you must use
the ‘wafting’ method when sampling the odor of your product as shown:
CP Chemistry
Theodore Roosevelt High School
Lab #4-6
Procedure
1.
2.
Prepare a water bath by filling a 400 mL beaker half full with tap water. Place the beaker on a hot
plate to begin heating it.
Using the following table, determine three ester fragrances you will produce in this lab:
Alcohol
n-amyl alcohol
n-amyl alcohol
n-amyl alcohol
methyl alcohol
ethyl alcohol
ethyl alcohol
3.
4.
5.
6.
7.
8.
9.
10.
Organic Acid
butyric acid (s)
salicylic acid (s)
acetic acid (aq)
salicylic acid (s)
butyric acid (s)
acetic acid (aq)
Ester Fragrance
apricot
pineapple
banana
wintergreen
apple
fruity
For your first fragrance, obtain 2 mL of the necessary alcohol and add it to a small test tube.
If your ester fragrance requires solid acid, obtain 1.0 g of acid and add it to the test tube. If your
ester fragrance requires liquid acid, obtain 2.0 mL of acid and add it to the test tube.
Carefully add 1.0 mL of concentrated sulfuric acid to the test tube. (Your teacher will perform this
step.)
Gently tap the bottom of the tube to mix the reactants in a safe manner.
Place the test tube in the water bath and allow it to be heated for one minute.
Check for any possible odor of an ester by using the ‘wafting’ method. Record your observations.
If no odor is detected, allow the test tube to remain in the water bath for 5-10 more minutes.
Repeat steps #3-8 for your second and third ester fragrances.
If an odor still cannot be detected, cover the test tube with a small piece of aluminum foil, label it
with your or your lab partner’s name, and leave it to sit overnight.
Additional Clean-up and Disposal
1.
DO NOT POUR ANY CHEMICALS DOWN THE SINK. Instead, dispose of any remaining
residue in your test tubes in the waste beaker.
Questions
1.
Show the balanced reaction for the production of each of the esters that you formed in this lab.
2.
Using the directions in the introduction, name the three esters that you produced in this lab.
3.
What is the purpose of using concentrated sulfuric acid, which is dangerous, instead of dilute
sulfuric acid or a weak acid, which would be safer?
Errors
Describe two possible errors you may have committed in this lab that may have somehow affected your
results. Explain the specific steps you will take to avoid each of these errors in the future.
Conclusion
Write two or more paragraphs summarizing your results and examining the validity of your prediction.
CP Chemistry
Theodore Roosevelt High School
Making Artificial Fragrances Lab workspace:
Lab #4-6
CP Chemistry
Theodore Roosevelt High School
Lab #4-7
Purifying Water – Capstone Lab
Introduction
In the Midwest, most of the water we use in our homes comes from
underground aquifers, but in many large cities, water is drawn from
rivers and lakes. Water from these natural sources can contain soil,
toxic substances, harmful bacteria and other impurities that must be
removed before we can drink it. When water is treated for drinking, it is
first allowed to settle in giant tanks to allow large particles to fall to the
bottom. The water is then treated to remove other suspended matter to
produce clear water.
In this capstone lab, you will first research and then perform a chemical purification procedure to
produce clear water using a sample from the Cuyahoga River. You will then judge your success based
on your water’s clarity/turbidity, odor, pH, total dissolved solids, and the overall complexity of your
chemical procedure. You will NOT drink your water; you would need to apply additional treatment in
order to make it potable, or safe for drinking.
Purpose
To remove impurities from a sample of water from a local water source.
Equipment
Determine all equipment you will use and list it in your lab write-up.
Materials
Determine all materials you will use and list them in your lab write-up.
Safety Considerations
• Sometimes chemicals from previous labs still remain in glassware and on other lab equipment;
wash all lab equipment before and after performing this lab.
• Wash your hands thoroughly after completing this lab.
Procedure
As you perform the lab, record your procedure steps, and then describe them in your lab write-up.
Data
Record all pertinent data and include it in your lab write-up.
Errors
Describe two possible errors you may have committed in this lab that may have somehow affected your
results. Explain the specific steps you will take to avoid each of these errors in the future.
Conclusion
Write two or more paragraphs summarizing and explaining your results, as well as critically analyzing
your procedure methods.
CP Chemistry
Theodore Roosevelt High School
Purifying Water Capstone Lab workspace:
Lab #4-7
Appendices
Chemistry
SI Prefixes Table
Prefix Symbol
Base Unit Multiplier
In Words
Exponential
yotta
Y
1,000,000,000,000,000,000,000,000
septillion
1024
zetta
Z
1,000,000,000,000,000,000,000
sextillion
1021
exa
E
1,000,000,000,000,000,000
quintillion
1018
peta
P
1,000,000,000,000,000
quadrillion
1015
tera
T
1,000,000,000,000
trillion
1012
giga
G
1,000,000,000
billion
109
mega
M
1,000,000
million
106
kilo
k
1,000
thousand
103
hecto
h
100
hundred
102
deca
da
10
ten
101
1
–
(base unit)
deci
d
0.1
tenth
10-1
centi
c
0.01
hundredth
10-2
milli
m
0.001
thousandth
10-3
micro
µ
0.000001
millionth
10-6
nano
n
0.000000001
billionth
10-9
pico
p
0.000000000001
trillionth
10-12
femto
f
0.000000000000001
quadrillionth
10-15
atto
a
0.000000000000000001
quintillionth
10-18
zepto
z
0.000000000000000000001
sextillionth
10-21
yocto
y
0.000000000000000000000001
septillionth
10-24
•
•
•
To convert FROM a base unit TO a prefix unit, MULTIPLY by the Base Unit Multiplier.
To convert TO a base unit FROM a prefix unit, DIVIDE by the Base Unit Multiplier.
To convert FROM a prefix unit TO another prefix unit, first MULTIPLY, then DIVIDE.
From http://www.essex1.com/people/speer/large.html:
"When the metric system was devised in the late 1700's there was no particular need for very large or very small
numbers. It was already customary to count in thousands and millions, and to use commas to set off the extra zeros in groups
of three, as we still do today. In the two centuries since that time we have learned to measure objects and distances, both
large and small, to the limits of nuclear particles and astronomical bodies, and to count from pennies to the US national debt.
The metric measurements are all in decimal form, and are used very consistently from one parameter to another. (Parameters
are things that you measure, such as: length, mass, charge, density, heat, temperature, etc.)
The mass of the earth is 5983 Yg (yottagrams), and it gains another 40 Gg (gigagrams) every year from captured
meteorites and cosmic dust. The average distance to the moon is 384.4 Mm (megameters). The average distance to the sun
is 149.5 Gm (gigameters). The wavelength of yellow light is 590 nm (nanometers). The diameter of a hydrogen atom is about
70 pm (picometers). The mass of a proton is about 1.67 yg (yoctograms), and that of an electron about 0.000 91 yg
(yoctograms).
Converting within the metric system becomes very easy with a little practice. It is simply a matter of moving the
decimal the proper number of places, in the correct direction! For example: 27 000 000 000 grams would be 27 gigagrams,
and 0.000 000 045 meters would be 45 nanometers. If you try to do similar problems in the British system, it becomes much
more difficult. Try the following: How many inches are there in 186,000 statute miles? How many avoirdupois ounces are there
in 82 dry tons? (Realize that there are also nautical miles, troy ounces, and liquid tons in the British system.) Answers:
11,785,000,000 and 2,624,000."
Chemistry
Useful Equations and Constants
Matter & Energy
D=
€
°C = K – 273; K = °C + 273
m
V
1 atm = 101.3 kPa = 760 mmHg = 14.7 PSI
Accuracy, Precision & Error
% error =
theoretical - actual
x 100%
theoretical
% yield =
actual
x 100%
theoretical
€
€
Gas Laws
STP = 0° C at 1 atm
Stoichiometry
6.02 x 1023 particles = 1 mole
Nuclear Chemistry
1 mole of gas at STP = 22.4 L
n=
t total
T1 2
Thermochemistry
fraction remaining =
q = CmΔT
€
1 cal = 4.184 J
CH2O = 4.184 J g°C
€
Concentration of Solutions
€
€
€
 1 n
A f = Ai ×  
2
A 
log f 
 Ai 
n=
1
log 
2
Acids & Bases
1 Af
=
2 n Ai
Chemistry
Ions Handout
Element
Ion Name
Symbol
Hydrogen
Cesium
Lithium
Potassium
Rubidium
Silver
Sodium
Barium
Beryllium
Calcium
Magnesium
Strontium
Zinc
Aluminum
Bromine
Chlorine
Fluorine
Hydrogen
Iodine
Oxygen
Selenide
Sulfur
Arsenic
Nitrogen
Phosphorus
Hydrogen ion
Cesium ion
Lithium ion
Potassium ion
Rubidium ion
Silver ion
Sodium ion
Barium ion
Beryllium ion
Calcium ion
Magnesium ion
Strontium ion
Zinc ion
Aluminum ion
Bromide ion
Chloride ion
Fluoride ion
Hydride ion
Iodide ion
Oxide ion
Selenide ion
Sulfide ion
Arsenide ion
Nitride ion
Phosphide ion
H
+
Cs
+
Li
+
K
+
Rb
+
Ag
+
Na
2+
Ba
2+
Be
2+
Ca
2+
Mg
2+
Sr
Zn2+
3+
Al
–
Br
–
Cl
–
F
H–
–
I
2–
O
2–
Se
2–
S
3–
As
3–
N
3–
P
Multiple Charge Ions
Chromium
Chromium (II) ion
Chromium (III) ion
Cobalt
Cobalt (II) ion
Cobalt (III) ion
Copper
Copper (I) ion
Copper (II) ion
Iron
Iron (II) ion
Iron (III) ion
Lead
Lead (II) ion
Lead (IV) ion
Manganese Manganese (II) ion
Manganese (III) ion
Mercury
Mercury (I) ion
Mercury (II) ion
Tin
Tin (II) ion
Tin (IV) ion
+
Symbol
2+
Cr
3+
Cr
2+
Co
3+
Co
+
Cu
2+
Cu
2+
Fe
3+
Fe
2+
Pb
4+
Pb
2+
Mn
3+
Mn
+
Hg
2+
Hg
2+
Sn
Sn4+
Polyatomic Ion Name
1+
Formula
Ammonium ion
NH4
Hydronium ion
H3 O
+
+
1–
Acetate ion
Amide ion
Chlorate ion
C2 H3 O2
NH2–
–
ClO3
Chlorite ion
Cyanate ion
Cyanide ion
Dihydrogen phosphate ion
Formate ion
Hydrogen carbonate (bicarbonate) ion
ClO2
OCN–
–
CN
–
H2PO4
CHO2–
–
HCO3
Hydrogen sulfate (bisulfate) ion
HSO4
Hydrogen sulfite (bisulfite) ion
HSO3
Hydroxide ion
Hypochlorite ion
Nitrate ion
OH
–
ClO
–
NO3
Nitrite ion
Perchlorate ion
Permanganate ion
Thiocyanate ion
NO2
ClO4–
–
MnO4
NCS–
–
–
–
–
–
2–
2–
Carbonate ion
CO3
Chromate ion
CrO4
Dichromate ion
Cr2O7
Hydrogen phosphate ion
Hydrogen phosphite ion
Oxalate ion
HPO4
HPO32–
2–
C2 O4
Peroxide ion
O2
Silicate ion
SiO3
Sulfate ion
SO4
Sulfite ion
Thiosulfate ion
SO3
S2O32–
3–
2–
2–
2–
2–
2–
2–
2–
Arsenate ion
Borate ion
Phosphate ion
AsO43–
BO33–
3–
PO4
Phosphite ion
PO3
3–
–
* “n-“ represents standard straight-chain hydrocarbon
1
3
4
5
6
8
9
10
11
www.webelements.com
7
12
13
14
15
16
WebElements: the periodic table on the world-wide web
2
17
18
fluorine
Ne
4.0026
neon
2
helium
oxygen
F
15.999
sulfur
Cl
18.998
chlorine
36
39.948
krypton
Ar
20.180
argon
10
nitrogen
O
14.007
phosphorus
S
35
35.453
bromine
9
carbon
N
12.011
silicon
P
34
32.065
selenium
8
boron
C
Si
33
30.974
arsenic
7
element name
B
Al
32
28.086
germanium
6
symbol
31
26.982
gallium
5
beryllium
atomic weight (mean relative mass)
30
zinc
18
29
copper
17
28
nickel
16
27
cobalt
15
26
iron
14
25
manganese
108
190.23
hassium
77
102.91
iridium
Ir
109
110
111
192.22
195.08
196.97
meitnerium darmstadtium roentgenium
112
50
72.61
tin
51
74.922
antimony
52
78.96
tellurium
53
79.904
iodine
113
114
115
116
117
118
204.38
207.2
208.98
[209]
[210]
[222]
ununtrium ununquadium ununpentium ununhexium ununseptium ununoctium
54
83.80
xenon
49
69.723
indium
Xe
48
I
86
131.29
radon
65.38
cadmium
85
126.90
astatine
47
84
127.60
polonium
63.546
silver
83
121.76
bismuth
46
82
118.71
lead
58.693
palladium
81
114.82
thallium
45
80
112.41
mercury
58.933
rhodium
79
107.87
gold
44
78
106.42
platinum
Pb Bi Po At Rn
55.845
ruthenium
76
101.07
osmium
43
75
[98]
rhenium
42
51.996
54.938
molybdenum technetium
74
95.96
tungsten
107
186.21
bohrium
Sn Sb Te
Pt Au Hg Tl
Cr Mn Fe Co Ni Cu Zn Ga Ge As Se Br Kr
13
24
chromium
atomic number
1.0079
lithium
Be
10.811
aluminium
4
Li
12
9.0122
magnesium
vanadium
23
titanium
V
22
scandium
Ti
41
50.942
niobium
73
92.906
tantalum
39
72
91.224
hafnium
106
183.84
seaborgium
W Re Os
105
180.95
dubnium
200.59
ununbium
Zr Nb Mo Tc Ru Rh Pd Ag Cd In
71
104
[268]
[271]
61
[272]
[270]
[276]
[281]
[280]
[285]
[284]
[289]
[288]
[293]
70
ytterbium
69
thulium
68
erbium
67
holmium
66
dysprosium
65
terbium
64
gadolinium
63
europium
62
samarium
91
140.91
protactinium
92
144.24
uranium
93
[145]
neptunium
94
150.36
plutonium
95
151.96
americium
96
157.25
curium
97
158.93
berkelium
98
162.50
californium
99
164.93
einsteinium
100
167.26
fermium
101
168.93
mendelevium
102
173.06
nobelium
[237]
[244]
[243]
[247]
[247]
[251]
[252]
[257]
[258]
[259]
Np Pu Am Cm Bk Cf Es Fm Md No
—
[294]
[267]
60
praseodymium neodymium promethium
59
Rf Db Sg Bh Hs Mt Ds Rg Uub Uut Uuq Uup Uuh Uus Uuo
58
cerium
[262]
57
90
140.12
thorium
U
89
238.03
232.04
231.04
[227]
Ac Th Pa
138.91
actinium
La Ce Pr Nd Pm Sm Eu Gd Tb Dy Ho Er Tm Yb
lanthanum
Lr
103
174.97
178.49
lawrencium rutherfordium
Lu Hf Ta
88.906
lutetium
Y
21
24.305
calcium
Sc
40
47.867
zirconium
20
22.990
potassium
Ca
44.956
yttrium
19
K
38
40.078
strontium
Na Mg
3
11
6.941
sodium
1
hydrogen
He
Key:
H
57-70
*
89-102
37
[226]
**
39.098
rubidium
56
87.62
barium
Rb Sr
55
85.468
caesium
88
137.33
radium
Cs Ba
87
132.91
francium
[223]
Fr Ra
*lanthanoids
**actinoids
Symbols and names: the symbols and names of the elements, and their spellings are those recommended by the International Union of Pure and Applied Chemistry (IUPAC - http://www.iupac.org/). Names have yet to be proposed for the most recently
discovered elements beyond 112 and so those used here are IUPAC’s temporary systematic names. In the USA and some other countries, the spellings aluminum and cesium are normal while in the UK and elsewhere the common spelling is sulphur.
Group labels: the numeric system (1–18) used here is the current IUPAC convention.
Atomic weights (mean relative masses): Apart from the heaviest elements, these are the IUPAC 2007 values and given to 5 significant figures. Elements for which the atomic weight is given within square brackets have no stable nuclides and are represented
by the element’s longest lived isotope reported at the time of writing.
©2007 Dr Mark J Winter [WebElements Ltd and University of Sheffield, webelements@sheffield.ac.uk]. All rights reserved. For updates to this table see http://www.webelements.com/nexus/Printable_Periodic_Table (Version date: 21 September 2007).