Alchemy Lab - Solon City Schools

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Honors Chemistry
Unit 1
Early chemists describe
the first dirt molecule
 What is chemistry?
 Elements to Memorize!
 Polyatomic Ions to Memorize!
 Chemistry Careers
 Scientific Method
 Observation Lab
 Lab Safety
 Lab Equipment
 Alchemy Lab
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At the conclusion of this unit, the student will be able to:
1.
2.
3.
4.
Identify and describe the development 6 branches of chemistry out of alchemy.
Distinguish between pure research, applied research, and technology.
Use the scientific method to solve various problems.
Use appropriate safety/lab equipment and procedures in the science classroom
We are looking for:
1. Ability to distinguish and identify various scenarios as organic, physical, biochem., analytical,
inorganic, theoretical chemistry.
2a. Pure research is learning for the sake of knowing.
2b. Applied research is using the knowledge gained from pure research to solve a specific problem.
2c. Technology is using the knowledge gained from pure research to improve the quality of life.
3a. Identify a problem.
3b. Create a hypothesis.
3c. Identify the independent and dependent variables, and control.
3d. Write a procedure.
3e. Collect and analyze data/observations and distinguish between qualitative and quantitative
observations.
3f. Formulate a conclusion.
4a. Identify the safety features of the room.
4b. Correctly light and adjust a Bunsen burner.
4c. Identify incorrect behavior in a lab scenario.
4d. Identify names and uses for lab equipment.
4e. Demonstration of safety procedures in the lab.
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How Chemistry Began
Throughout
history
people
have
tried
environment to improve their way of life.
to
alter
their
Such “tinkering” has
often lead to unexpected results.
4000 B.C.
Mesopotamian Cultures
Irrigation
2000 B.C.
Egyptians
Metallurgy and Embalming
400 B.C.
Greeks
Understanding of Matter
600 A.D.
India
Steel
1000 A.D.
Chinese
Gunpowder
This “tinkering” has fulfilled two needs:
 To understand the world around them.
 To improve and protect our lives.
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Chemistry
4
Research
Research is done for different reasons. The type of research pursued is dependent uon what
information is important/needed.
Basic or Pure Research:
 The main goal of this type of research is to gain new knowledge about a chemical or
process, just for the sake of knowledge.
 Chance discoveries can result from basic research.
 “I wonder what would happen if …”
Applied Research:
 The main goal of this type of research is to solve a specific problem.
 Example: CFC’s (chloro fluor carbons) in refrigerants destroyed the ozone so chemists
formulate new refrigerants.
Technological Development:
 This type of research involves the making and use of products that improve the quality of life.
 Development can result from basic research.
Example: Teflon coating.
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Ag
Li
Al
Mg
Ar
Mn
As
Mo
Au
N
B
Na
Ba
Ne
Be
Ni
Br
O
C
P
Ca
Pb
Cd
Pt
Ce
Ra
Cl
Rb
Co
Rn
Cr
S
Cs
Sb
Cu
Sc
F
Se
Fe
Si
Fr
Sn
Ga
Sr
Ge
Ti
H
U
He
V
Hg
W
I
Xe
K
Zn
Kr
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Introduction
Polyatomic ions are charged molecules. The atoms within a polyatomic ion are usually very tightly bound together, so
the ion retains its identity within ionic compounds and over the course of many chemical reactions.
Because polyatomic ions are basic building blocks of so many ionic compounds, learning the names, charges, and
formulas of the most common polyatomic ions is absolutely essential before many other skills can be mastered.
Most common polyatomic anions occur in "families". All members of the family share the same central element and
the same charge. There are three common types of variations within the family:



Other
Different members of the family can have different numbers of oxygens.
Each member of the family can combine with hydrogen ions to partially neutralize their negative charge.
Some members of the family can have sulfur substituted for oxygen.
variations exist but are less common.
Table of common polyatomic:
Polyatomic Name
Polyatomic Ion
Ammonium
NH4+
Hydronium
H3O+
Acetate
C2H3O2-
Bromate
BrO3-
Bicarbonate
HCO3-
Chlorate
ClO3-
Hydroxide
OH-
Iodate
IO3-
Nitrate
NO3-
Permanganate
MnO4-
Carbonate
CO32-
Chromate
CrO42-
Sulfate
SO42-
Phosphate
PO43-
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Common naming practices
If you can remember the formula of the ion whose name ends with ate, you can usually work out the
formulas of the other family members as follows:
modify stem name
with:
meaning
examples
per-, -ate
same charge, but contains one more oxygen than
perchlorate, ClO4-
-ate form
perbromate, BrO4-
a common form, containing oxygen
chlorate, ClO3-
-ate
nitrate, NO3sulfate, SO42-ite
one less oxygen than -ate form
chlorite, ClO2sulfite, SO32nitrite, NO2-
hypo-, -ite
same charge, but contains one less oxygen than
hypochlorite, ClO-
the -ite form
hypobromite, BrO-
Some anions can capture hydrogen ions. For example, carbonate (CO32- can capture an H+ to produce
hydrogen carbonate HCO3- (often called bicarbonate). Each captured hydrogen neutralizes one minus
charge on the anion.
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NICK the CAMEL ate a CLAM for SUPPER in PHOENIX



Ex)
Underlined letter represents the symbol of the element.
The consonants represent the number of oxygen present with the symbol.
The vowels represent the number of negative charge.
Underlined letter = N
Number of consonants = 3
Number of vowels
=1
represents oxygens
represents charge
NO3-
Ex)
Underlined letter = P
Number of consonants = 4
Number of vowels
=3
Nitrate
represents oxygens
represents charge
PO43-
Phosphate
Camel
Carbonate
Clam
Chlorate
Supper
Sulfate
Another One!!!
IZZY the BRAT CRAVED MINTS
Izzy
IO3-
Iodate
Brat
Bromate
Craved
Chromate
Mints
Permanganate
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Career Report
Directions: Read the handout given to you about a career in chemistry and answer the following questions. You should
use this information to write a job advertisement as a blog on my website.
 You must post your job advertisement to the blog by the end the day on ___________!
 You will respond to 3 jobs starting on _______________ You have until 3:00 on __________________ to
respond to 3 jobs. See the blog for further instructions!
1. Name of chemical career
2. How much education/training do you need to qualify for this job?
3. How much money can I make doing this job?
4. Who is best suited for this job?
5. What is a typical day like working this job like?
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Scientific Method
1.
Define the problem
 You can’t solve a problem until you know exactly what the problem is
2.
Collect background information
 What do I know and what will I need to know about the problem?
3.
Formulate a hypothesis
 A possible solution to the problem – simple is better usually!
4.
Test the hypothesis
 Perform an experiment to see if your hypothesis works.
5.
Data Analysis
 Collect data and make good observations about what is happening.
6.
Draw conclusions
 Evaluate what was found and let everyone who is interested know what you found.
If it worked – GREAT!
If it didn’t work – start again!!
Terms of the Scientific Method
Observation –
 Statement of fact
 Obtained by using one of the five senses
 Qualitative (words) / Quantitative (numbers)
Inference –
 Attempts to make one think
 Is in the form of a question
Hypothesis –
 An explanation that can be tested
 A prediction based on observations
 Must state the conditions (variables) and explains why a phenomenon is occurring.
 Can be an educated guess.
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Law 





Set of related observations of nature.
Generalizes a body of observations.
Proven to be true in each and every case.
Governs a simple or single action.
Observation that will lead to the use of the scientific method to explain why the observation occurred.
Many times expressed with mathematical equations.
Example: When a gas is heated, it will expand.
Theory –
 Explanation of why a set of related observations occurs.
 Based on proven hypotheses
 Verified by multiple groups of researchers
 Tries to explain a whole series of related phenomena
 Proven within reasonable doubt
 More complex than a law
Example: The kinetic molecular theory is used to explain why a gas will expand when heated.
Law (Simple Relationship)

Inference  Hypothesis

Theory (Complex)
Testing the Hypothesis Research Models limit the number of variables to two
o
Independent Variable – The condition that is to be studied. It will be changed in the
experiment. It is controlled by the experimenter – "I control it".
o
Dependent Variable – It will be affected by the independent variable. It cannot be
controlled by the experimenter; think results of the experiment.

Control Group-The group that is represented in a normal situation; does not receive the
experimental treatment.

Experimental Group(s)-The group that receives the experimental treatment, the independent
variable.

Constants- all the other conditions that must remain the same (constant) for both groups.
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Writing If / Then Hypothesis Statements
The “IF” part of the statement:
 Mention Independent and dependent variables
Link: are related, depend on each other, can be
correlated
The “THEN” part of the statement:
 Make an educated guess how they are related or what will happen in the experiment
If Variable 1 and Variable 2 are related then
state the relationship you believe exists between the two variables.
Example: If plant growth and amount of water are related, then the plant will grow taller the more it is watered.
Independent variable = water
Dependent variable = plant growth
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Chemistry Lab Experience
"Scientific Method"
Title: "Observing And Questioning
I. Problem:
How does a chemist develop his skills of observation and of developing hypotheses?
II. Background Information:
A natural characteristic of all human beings is curiosity. We have all wondered how a watch keeps time or how
the automobile engine uses the energy stored in gasoline.
To chemists, the questions always revolve around the basic composition of matter and how we can change it to
benefit mankind. The more we learn about nature and how nature works, the more specific our questions can become.
In this experiment, you will observe some changes in matter. You will then propose some questions you would
like answered to gain more understanding about the changes.
III. Hypothesis:
In your own words what do you think will happen during this lab?
IV. Test Hypothesis:
A. Materials:
spatula
150 mL beaker
graduated cylinder
“X” crystals
liquid “Y”
liquid “Z”
metal foil
stirring rod
safety glasses
B. Procedure:
1. Using the very tip of your spatula, fill the tip of your spatula with crystals of "X" and place them in a
clean, dry 100-150 mL beaker.
2.
Measure exactly 21.2 mL of liquid "Y" into your graduated cylinder. Use your dropper pipette with
a little of "Y" in a beaker to make this exact. Bring this with your observation page to your teacher
for grading. Make certain that you and your lab partner agree on the volume. You will lose 1 point
for each 1-2 tenths you are over or short of the required amount of liquid. (4/2 points)
3. Add liquid "Y" to the beaker containing "X". Do not stir. Observe for about 3 minutes. Caution:
These crystals are poisonous; avoid contact and rinse spills with plenty of water.
4. Stir the crystals until they dissolve completely. There should be enough of "X" to turn the color of
"Y".
5. Obtain a piece of metal foil. The piece should be approximately 2 cm x 2 cm square. Use your ruler
to estimate the size.
6. Loosely crumple the metal foil and place in into the beaker with the dissolved crystals. If the foil
floats, press it down with a stirring rod. After the reaction is complete, discard the liquid and rinse
the beaker with water.
7. Measure about 25 mL of liquid "Z" and place it into a clean 100/150 mL beaker.
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8. Obtain another piece of metal foil. The piece should be approximately 2 cm x 2 cm square. Crumple
it loosely and place it in liquid "Z". Caution: Liquid "Z" causes burns and can injure the eyes.
Avoid contact and rinse any spills with plenty of water. Do not inhale fumes. The reaction
starts slowly, so allow enough time for your reaction to go to completion.
The following are to be written of a separate sheet of paper!
V. Record Observations:
Prepare a data table like the one demonstrated on the overhead.
VI. Draw Conclusions:
A. Questions:
1. Write 8 questions (inferences) that you would like answered about this experiment.
2. Write answers (hypotheses) for all 8 questions.
3. Describe two major barriers that prevent you from discussing and understanding the changes you saw
in this experiment.
B. Summary Paragraph
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Safety Contract for Honors Chemistry
The National Science Teachers Association urges that students be required to review and sign a contract that defines
acceptable behavior in a school science setting.
The purpose of this contract is to make the student aware of his/her responsibility for
laboratory safety.
Students should realize the implications of improper laboratory behavior. Courts have ruled that students can be just as
guilty of negligence as teachers in laboratory accidents. These guidelines are to keep you and your classmates safe.
I will:
1.
2.
3.
4.
5.
6.
Follow all instructions given by the teacher.
Protect eyes, face, hands, and body when involved in science experiments.
Carry out good housekeeping practices.
Know where to get help fast.
Know the location of the first aid, eye wash, fire extinguisher and fire blanket.
Conduct myself in a responsible manner at all times.
I, _________________________, have read and agree to follow the safety regulations set forth above and below on this
contract. I will closely follow the oral and written instructions provided by the teacher and/or school administration.
Date: ______________
Student Signature: ____________________________
Date: ______________
Parent Signature: ____________________________
Laboratory Safety Rules
1. Wear proper eye protection at all times during laboratory activity. Let instructor know if you wear contact
lenses. Know the location of the eye wash equipment.
2. Confine or tie hair that reaches the shoulders – hair is flammable!
3. DO NOT eat, drink or chew gum in the laboratory. Never taste anything unless specifically instructed to do so by
the teacher. No chemicals are ever to be taken from the laboratory.
4. Never engage in horseplay or practical jokes.
5. Footwear should cover the whole foot.
6. Avoid inhaling chemical fumes. All chemicals are dangerous unless they are known to be otherwise.
7. The teacher is to be notified immediately in case of an accident, no matter how trivial it may appear.
8. Know the locations of the fire extinguisher, fire blanket, eye wash, safety shower, first aid kit and clinic.
9. Notify instructor immediately of any spills on your clothing.
10. Dispose of items as instructed by the teacher. Only certain chemicals can be put down the drain safely.
11. Never return chemicals to their original container, unless told to do so.
12. Never point the open end of a test tube being heated at anyone, including yourself.
13. Always add acid to water (AA). This is particularly true of concentrated sulfuric acid.
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Name ___________________________________
Class Period__________
Safety Scenarios
The diagram below and the diagram on the back, show students performing laboratory activities. Study each
diagram and write in the spaces all of the proper and improper lab techniques you can pick out. Be prepared
to discuss your answers.
Picture 1
Proper Techniques
Improper Techniques
1.
1.
2.
2.
3.
3.
4.
4..
5.
5.
6.
6.
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Picture 2
Proper Techniques
Improper Techniques
1.
1.
2.
2.
3.
3.
4.
4.
5.
5.
6.
6.
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Lab Safety Stories
On a separate sheet of paper, list of all the safety violations for each story.
Story #1 – there are at least 10 violations in this story.
Mike was the first to arrive at the laboratory. He had just
come from playing basketball and still had on his gym shorts and
sandals. Wanting to finish early, he began to work on the assigned lab.
Mike had not read the lab so he quickly skimmed the directions. He needed some
water to prepare a solution. There was an unlabeled bottle of clear liquid on the
bench, so he tasted it to see if it was water. It was bitter and burned his mouth.
He spit the liquid out and dumped the bottle into the sink. After preparing his
solution, he got out his lunch and began to eat while getting the balance out of the
cupboard. When he put the balance on the lab bench, he knocked over the beaker
containing the solution and it fell onto the floor and broke. He pushed the broken
pieces under the bench and got another breaker out of the supply cabinet.
He got bored so he took 2 bottles of chemicals off the teacher’s desk and put
several drops of each chemical into a beaker. He used his finger to stir the
mixture. He discarded the liquid in his beaker down the sink and then returned
the beaker to his lab drawer.
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Story #2 – there are at least 6 violations in this story.
Kate decided to do the experiment right away. She put her
books, lunch and purse on one side of the lab bench so she
could work on the other half. The lab called for her to heat some water. She
turned on the gas at the gas outlet, got the Bunsen burner out of the cabinet
and lit it. To keep the clutter down, she threw the match into the garbage. She
was wearing a loose, long sleeved sweater. She reached over the flame to get a
bottle of chemical that she needed from the other side of the lab bench. Her
sleeve caught on fire. She screamed for help. When no one responded, she ran
out of the classroom with her sleeve ablaze.
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Lighting a Bunsen Burner
1. Attach the burner hose to the gas outlet at the wall.
2. Close the air and gas valves on the burner. (Turn them clockwise as
you look at them)
3. Light a match and open the gas outlet at the wall/table.
4. Open the gas valve on the
burner until you hear a faint
hissing sound of gas escaping.
5. Light the burner using
matches or a lighter.
6. Adjust the air valve until you
have a good inner cone and
an outer cone about 5 cm
high.
Air Valve
7. Close the gas outlet (at the
Wall/table) to extinguish the flame.
Gas Valve
A Bunsen burner is not a
candle. NEVER blow it out.
Gas Outlet
 The gas valve adjusts the height of the flame
 The air valve changes the color (temperature) of the flame
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Alchemy Lab
I.
II.
III.
Problem: Can I change a penny into gold?
Hypothesis: If alchemists are associated with turning metals into gold, then when I turn a penny to
gold, I am an alchemist!
Experiment:
a. Materials:
Bunsen burner
2 metal rings
ring stand
150 mL beaker
graduated cylinder
spatula
250 mL beaker
safety glasses
steel wool
5 pennies (pre 1982)
stirring rod
wire gauze
zinc (granulated)
crucible tongs
3.0 M sodium hydroxide (NaOH)
b. Procedure:
1. Set up a double ring stand to heat a 150 mL beaker. Make sure the beaker is steady on the
ring stand/wire gauze and the second ring is around the middle of the beaker. The bottom
ring/wire gauze should be about 5 cm above the Bunsen burner.
2. Using steel wool, buff your pennies. Keep one penny as a control for later comparisions.
3. Place a spatula tip full of zinc into the beaker.
4. Carefully pour 25.0 mL of 3.0 M sodium hydroxide (NaOH) into the same 150 mL beaker.
Put the beaker on the ring stand.
5. Light the Bunsen burner. Using a blue flame, adjust the flame so the tip just touches the
wire gauze. Bring the solution to “near” boiling. Lower the flame to maintain the solution
at “just under” boiling. Move the Bunsen burner out from under the beaker if needed.
DO NOT HEAT TO DRYNESS!!
CAUTION: SODIUM HYDROXIDE IS DANGEROUS IF IT CONTACTS YOUR SKIN AND CAN CAUSE
BLINDESS IF SPLASHED INTO EYES. THE FUMES ARE IRRITATING TO THE LUNGS AND WILL
CAUSE COUGHING. THEREFORE – DO NOT BOIL – THERE SHOULD BE NO STEAM PRODUCED!
6. Using crucible tongs, carefully add no more than four pennies to the hot solution at one
time. Do not drop the pennies into the solution. It could cause the beaker to break or
cause the solution to splash out. Set the third penny aside as a control to compare to the
treated coins. Carefully stir the solution with a stirring rod. Rotate the coins in the hot
solution by using your crucible tongs.
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7. Carefully stir the solution with a stirring rod. Rotate the coins in the hot solution by using
the crucible tongs.
8. Make some observations about what is happening to the pennies in the beaker.
9. Fill a 250 mL beaker about half full with tap water.
10. With the crucible tongs, remove the pennies when they have completely turned to a silver
color. Dip them into the beaker of water to rinse. Dry them in a paper towel. Set one aside
for later comparisons.
11. Carefully move the Bunsen burner out from under the ring stand.
12. To turn the pennies to gold, gently heat them in the coolest part of the burner flame. Hold
them vertically with the crucible tongs – DO NOT OVERHEAT! If the coins turn brown, you
overheated them!
13. After the appearance of the coin has changed, place it in the beaker of water. Then remove,
rinse, and dry it.
14. Record observations (in observation section) about changing the coin from silver to gold.
15. Clean up the equipment and work area. Return equipment to the proper location.
IV.
Observations:
V.
Conclusions:
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