Name, Date, Hr/Per_____________________________________________________________________
LAB SAFETY & CHAR. OF SCIENCE – UNIT 1 – INSTRUCTIONAL PACKET
UNIT 1 Vocabulary: Create notecards or a key-term foldable for Chapter 1 Vocabulary. Due __________________
Rules for Finishing Vocabulary
1. Vocabulary Cards.
a. Any sized note card may be used - you may choose to use full-sized cards bought in a store, or cut
cards in half. A piece of paper cut into EQUAL strips may also be used.
2. “Key-Term” Fold. - make tabs that you can open to reveal information beneath [this information can also be
found on page ______ of the biology textbook...which is viewable online...]
a. take out a sheet of lined paper
b. fold the paper in half from left to right
i. a "hot-dog" fold will give you more terms per sheet
ii. a "hamburger" fold will give you more space for definitions per term
c. using scissors, start from the first full line at the BOTTOM of the paper and cut every few lines [4 lines
is recommended] from the RIGHT edge to the center
d. do NOT cut the bottom layer of the sheet, just the top layer
Unit 1 – Lecture 1: Lab Safety
Lab Safety:
- Definition:
Safety Equipment:
- Goggles
Proper attire:
- Examples:
-
First Aid Kit
-
Fire Blanket
-
Fume Hood
-
Fire Extinguisher
-
Safety Shower
-
Eyewash Fountain
1
Broken Glass:
- What to do?
Material Safety Data Sheet (MSDS):
NFPA Label:
- Red:
-
Yellow:
-
Blue:
-
White
ACIDS:
- Rule for mixing acid and water:
Student Use of the Lab:
- When is it appropriate?
-
When is it not appropriate?
Basic Chemistry Lab Equipment [see directions on next page]
Know the name of each piece and its basic use. There will be a quiz on this soon. This is not a complete listing of all
the equipment in our lab, but knowing the items on this list will prepare you for your next science class! See the
bottom of the right page for instructions.
Pipette [pipet] Filler
Pipette [pipet]
For exact volume measurements of liquids.
There are several styles of fillers used to
draw liquids into a pipette.
Never draw a liquid into a pipette with
your mouth!
Filter Flask
Erlenmeyer Flask
Used in conjunction with a
vacuum connection to a water
Used to contain reaction solutions.
faucet to speed up filtration.
Florence Flask
Volumetric Flask
Used to boil liquids.
Used to make solutions
Evaporating Dish
Watch Glass
Used to recover dissolved solids
Similar to an evaporating dish. Can be
by evaporation.
used to cover beakers.
2
Beaker
Graduated Cylinder
Used to contain chemical
Used to make accurate measurements
reactions
of liquid volumes.
Support Ring
Used to support glassware
above the lab table.
Crucible and Cover
Used as a container when
something requires strong
heating.
Wire Gauze
Will support glassware when
placed across a support ring.
Mortar and Pestle
To grind solids into powders.
Filter Funnel
When lined with filter paper,
used to filter suspended solids
from a liquid.
Chemical Spoons
To transfer solids from their
original bottle to a scale for
weighing.
Utility Clamp
Used to hold large test
tube or Florence flask
above the lab table.
Crucible Tongs
For picking up crucibles
and crucible covers ONLY.
Striker
Used to light a lab burner.
Not a toy noisemaker
during lab.
Test Tube Holder
To hold test tubes while
heating.
Wash Bottle
For washing solids out of a
container when filtering.
Hose Clamps
Used to close hoses by
pinching them together.
For the equipment, create a set of note-cards for studying OR create a “key term” type foldable. Include picture,
name, and description; it is recommended that you make multiple cards/folds for each item – you will have a quiz on
this soon on which you will be given a term, picture, or description and will need to be able to identify the other two
bits of information.
3
NAME:_____________________________________________________________ Period:______ DATE:__________
Hypothesis, Theory, or Law?
Mark each statement below as a Hypothesis (H), a Theory (T), or a Scientific Law (L) based on each of their
definitions. A Hypothesis is a testable prediction, or an educated guess, and must always be in the form of a
statement; never a question. Theories have some scientific evidence for their basis, but theories are in the condition
of having never been tested or that they cannot be tested. Scientific Laws are always true and can never be
disproved.
_____ 1. Dogs will eat all kinds of cheese.
_____ 6. “Tide” brand laundry detergent works better
than other brands.
_____ 2. Gravity affects all objects in the universe.
_____ 8. I like spinach, so I’ll probably like “Spinach
Pie” or “spirocopita”.
_____ 3. The sun will come up in the East tomorrow.
_____ 4. A moving railroad car will lose energy when
hitting a stationary railroad car.
_____ 9. The Universe started in a massive explosion
of time, matter, space, and energy.
_____ 5. Birds descended from dinosaurs through
evolution.
_____ 10. Energy can be converted from one form to
another.
_____ 6. The pool water is too cold to go swimming.
Unit 1 – Lecture 2: What is Science?
Science:
- Definition
Evidence:
- Definition
Data:
-
Qualitative
Reasoning
- Deductive
- Quantitative
-
Inductive
-
Inference
Hypothesis
Theory
Law
Ethics vs. Values
- Ethics:
-
Values:
Scientific Method:
- Definition:
Steps of the Scientific Method:
Format for a Hypothesis:
- If, Then
5
Types of Hypotheses:
- Hypothesis
-
Null Hypothesis
Tests Groups:
- Control Group
-
Experimental Group
Variables:
- Constants
-
Experimental Variable
-
Dependent Variable
Results:
-
Reproducible?
Practice Problems:
Practice with Experimental Design
MOUTHWASH: The makers of brand A
mouthwash want to prove that their mouthwash
kills more bacteria than the other 4 leading brands
of mouthwash. They organize 60 test subjects into
6 groups of 10 test subjects. The data for the
experiment is shown to the right.
IV: ____________________________________
mouthwash
used
none
A
B
C
D
E
time mouthwash
was in mouth
[n/a]
60 sec.
60 sec.
60 sec.
60 sec.
60 sec.
# of bacteria in
mouth (average)
135
23
170
84
39
81
DV: ___________________________________________________________________________________________
4 constants: ____________________________________________________________________________________
___________________________________________________________________________ ___________________
Control Group [if applicable]: ____________________________________________________ ___________________
Formulate a hypothesis for this experiment [4 important things!!!] ________________________________________
_______________________________________________________________________________________________
State the number of trials or repetitions______________Was the hypothesis correct? ________________________
Was this experiment controlled? ____________ Explain the rationale for your response. ______________________
_____________________ __________________________________________________________________________
What was the conclusion reached in the experiment? __________________________________ __________________
_______________________________________________________________________________________________
_____________________________________________________________________________________ __________
Suggest 4 possible sources of error for this experiment. _________________________________ _________________
__________________________________________________________________________ _____________________
____________________________________________________________________ ___________________________
6
Suggest an extension to the lab. [How could the knowledge gained from this experiment be further tested? – you
CANNOT repeat this experiment…] ___________________________________________________________________
_________________________________________________________________________ ______________________
_________________________________________________________________________ ______________________
_________________________________________________________________________ ______________________
IN THE GARDEN: Mary had observed that bean plants seemingly grew taller when fertilizer A was applied rather
than fertilizer B. The experiment designed tested bean plants to determine which type of fertilizer would produce
the tallest bean plants in a 90 day period. Three containers were used – each holding the same amount of soil and
100 beans seeds [each planted in the same way]. She placed all three containers on a covered back porch. Fertilizer
A was added to one container, fertilizer B to another, and no fertilizer in the last. Each was watered with the same
amount of water distributed in the same way over 90 days [every other day]. At the end of the 90 days, the
container of plants which received fertilizer A produced plants with an average height of 42.5cm. Fertlizer B plants
averaged 30cm, and the container receiving no fertilizer averaged 25cm in height.
IV: ____________________________________________________________________________________________
DV: _______________________________________________________________________ ____________________
4 constants: ____________________________________________________________________________________
___________________________________________________________________________ ___________________
Control Group [if applicable]: _______________________________________________________________________
Formulate a hypothesis for this experiment [4 important things!!!] ________________________________________
___________________________________________________________________________ ____________________
State the number of trials or repetitions______________Was the hypothesis correct? ________________________
Was this experiment controlled? ____________ Explain the rationale for your response. ______________________
_____________________ __________________________________________________________________________
What was the conclusion reached in the experiment? __________________________________ __________________
__________________________________________________________________________ _____________________
_____________________________________________________________________________________
Suggest 4 possible sources of error for this experiment. _________________________________
__________________________________________________________________________
_______________________________________________________________________________________________
Suggest an extension to the lab. [How could the knowledge gained from this experiment be further tested? – you
CANNOT repeat this experiment…] ___________________________________________________________________
_________________________________________________________________________ ______________________
_________________________________________________________________________ ______________________
_______________________________________________________________________________________________
7
Controls & Variables: The data to the right were collected from an
experiment that examined water potential of potato plant cells [ability
of water to move in and out of cells]. Water potential is dependent on
the concentration of the solution surrounding the cells. The mass of
each cell changes depending on the change of solution
concentration.
Beaker Contents Percent Change in Mass
Distilled Water
21.4
.2 M sucrose
6.9
.4 M sucrose
-4.5
.6 M sucrose
-12.8
IV: _____________________________________________________
.8 M sucrose
-23.0
DV: ____________________________________________________
1.0 M sucrose
-23.5
4
constants:
______________________________________________
___________________________________________________________________________ ___________________
Control Group [if applicable]: ____________________________________________________ ___________________
Formulate a hypothesis for this experiment [4 important things!!!] ________________________________________
___________________________________________________________________________ ____________________
State the number of trials or repetitions______________Was the hypothesis correct? ________________________
Was this experiment controlled? ____________ Explain the rationale for your response. ______________________
_____________________ __________________________________________________________________________
What was the conclusion reached in the experiment? ____________________________________________________
__________________________________________________________________________ _____________________
_____________________________________________________________________________________
Suggest 4 possible sources of error for this experiment. _________________________________
__________________________________________________________________________
____________________________________________________________________ ___________________________
Suggest an extension to the lab. [How could the knowledge gained from this experiment be further tested? – you
CANNOT repeat this experiment…] ___________________________________________________________________
_______________________________________________________________________________________________
_________________________________________________________________________ ______________________
_________________________________________________________________________ ______________________
8
Writing a Lab Report Activity
TITLE
PURPOSE
-
Gives Reader Idea of What Experiment is About
Sentence / Paragraph Format
Must Be a Statement
One Sentence Summary of What You’re Doing
BACKGROUND INFO
Sentence / Paragraph
Format
- Information Gathered On Topic
-
Identifies IV and DV
Identifies Control Group
IdentifiesAny Constants
HYPOTHESIS
- If, Then Statement
- Sentence / Paragraph Format
- Cannot Be A Question
MATERIALS & PROCEDURE
- List Format
DATA & OBSERVATIONS
- Tables, Charts, Graphs…
CONCLUSION
- Restates Purpose of Lab
- Summary of Results
- Contains Analysis [what do the results mean]
- Restate Hypothesis
- Support / Reject Hypothesis
- Suggestions for Improvement
- Extention to Lab
**First person language
should NEVER appear in a
lab report ANYWHERE.**
IV and DV are found
everywhere EXCEPT in
materials… [yes, they’re
even in procedure, really,
since you need to mention
how you are measuring
each].
Unit 1 – Lecture 3: The International System of Measurement
Metric System:
-
Definition
Why you don’t use it?
SI Prefixes:
-
Common prefixes (you need to know)
Practice Problems:
Base Units:
Length
-
Mass
-
Time
Derived Units:
-
Volume
o
-
Formula =
Density
o
Formula =
Metric Mania
[adapted from worksheet by T. Trimpe – sciencespot.net]
LENGTH:
1. What is the basic unit for length? ______________
2. Circle the best unit for measuring each distance:
a. Thickness of an eyelash: mm cm m
b. Length of a pencil: cm m km
3. Use a meter stick or metric ruler to find each measurement.
a. Width of this page ____________ mm or ____________ cm
b. Length of an unsharpened pencil _____________cm
4. Convert the following measurements:
a. 34 mm = _______ cm
b. 3 km = _______ m
MASS:
5. What is the basic unit for mass? ______________
6. Circle the best unit for measuring each mass:
a. Amount of spices in a batch of cookies: mg g kg
b. Your mass: mg g kg
c. 234 cm = _______ m
d. 35 m = _______ mm
c. Mass of 10 pennies: mg g kg
Use a triple-beam balance to find each measurement.
a. Mass of an ink pen __________ g b. Mass of a can of soda __________ g
8. Convert the following measurements:
a. 16 mg = _______ g
b. 4.7 kg = _______ g
c. 12,345 g = _______ kg d. 2 g = _______ mg
TEMPERATURE:
15. What is the basic unit for temperature? ______________
16. What are the freezing and boiling points for water on this scale? _______ _______
17. Circle the best choice:
a. Temperature on a hot summer’s day: 0⁰ 35⁰ 90⁰
b. Room temperature: - 20⁰ 0⁰ 20⁰
18. Convert the following measurements.
a. 90⁰ F = ______⁰ C
b. 45⁰ F = ______⁰ C
VOLUME:
19. What is the basic unit for volume? _______________
20. Circle the best unit for measuring each volume:
a. Amount of soda in 1 can: mL L
b. Water in a bathtub: mL L
21. Determine the volume for each object.
a. Use L x W x H to find the volume of a chalkboard eraser ___________ cm3
b. Use water displacement to find the volume of four marbles ____________ ml or ___________ cm3
22. Convert the following measurements:
a. 160 mL = _______ L
b. 23 kL = _______ L
c. 456 cL = _______ mL
d. 120 mL = _______ cm3
TIME:
23. What is the basic unit for measuring time? _______________
24. How many seconds are in:
a. 1 minute? _______ b. 6 hours? _______ c. 2 days? _______
DENSITY:
28. Would the objects with the following densities float, sink, or remain suspended in tap water?
a. 0.85 g/mL _______________ b. 1.0 g/mL _______________
c. 1.4 g/mL _______________ d. 0.92 g/mL _______________
16
Metric Conversion Word Puzzles
1. Below, write the prefixes for the metric system in order from left to right.
The numbers in the boxes after each section of problems below correlate to each of the problem numbers.
Complete the following problems. Next, find the term from those directly below which correlates with each problem
number. Once you have found the term that matches the answer, write the term in the box with contains the
number for the problem.
0.437
0.49
0.875
0.97
5
9.762
25
43.7
89
97.62
160
342
437
to
did
because
from
to
he
steak
jump
wanted
croak
Texas
his
bugs
500
970
1,600
2,500
4,000
4,300
16,000 25,000 56,000 97,620 .00437
.576
57.6
pond
frog
Paris
French
why
move
meals
tried
the
decide
served
with
flies
2. 4m = _______mm
5. 97cm = _______mm
8. 4.3km = _______m
3. 49cm = _______m
6. 25L = _______mL
9. 5mm = _______cm
4. 16kg = _______g
7. 437mg = _______g
10. 1.6L = _______mL
Sentence:
2
3
4
5
6
7
8
9
10
?
11. 87.5cm = _______m
14. 3.42m = _______cm
17. 97.62kg = _______g
12. 9762g = _______kg
15. 576L = _______kL
18. 2.5kL = _______L
13. 8.9cm = _______mm
16. 56g = _______mg
19. 4.37mg = _______g
Sentence:
11
12
13
14
15
16
17
19
20
17
HONORS METRIC CONVERSIONS
Although America tends to use the system which uses inches, feet, miles, etc – almost everyone else in the world
follows the “International System” – aka, the Metric System. The letters below represent some of the units in the
metric system. Feel free to use the blanks to fill in a word to help you remember the placement of each unit. A
common phrase for this is, “King Henry Died By Drinking Chocolate Milk.”
k___________h___________d___________b___________d___________c___________m___________
kilo
hecto
deca
[basic]
deci
centi
milli
[1,000]
[100]
[10]
[1]
[.1]
[.01]
[.001]
Because the metric system is a “base ten” system – meaning, it’s based on the number 10, you can use this small
chart to help you easily do conversions. Example: If I want to change a KILOmeter to a MILLImeter, I would move
the decimal 6 places to the right, because the “m” for milli- is six places to the right of the “k” for kilo. Circle the
“basic” units of measurement for solids, liquids, and length.
Kilogram _____
Meter _____
Gram _____
Milliliter _____
Millimeter _____
Liter _____
Kilometer _____
Centimeter _____
Milligram _____
Practice your conversions using the problems below – write your answer in the space provided.
Show your work.
1. 3.68 kg = __________ g
11. 2.75 km = ___________ cm
21. 2500 m = _______ km
2. 568 cm = __________ m
12. 455 cg = _____________g
22. 480 cm = _____ m
3. 8700 mL = __________ L
13. 3.5 hg = ____________g
23. 5 mL = _____ L
4. 25 mg = __________ g
14. 67 mm = ___________ m
24. 65 g = _____ mg
5. 0.101 cm = __________ mm
15. 0.005 kg = __________ cg
25. 5.6 kg = _____ g
6. 250 mL = __________ L
16. 2000 mg = _______ g
26. 50 cm = _____ m
7. 600 g = __________ kg
17. 5 L = _______ mL
27. 6.3 cm = _____ mm
8. 8900 mm = __________ m
18. 16 cm = _______ mm
28. 8 mm = _____ cm
9. 0.000004 m = ________ mm
19. 104 km = _______ m
29. 5.6 m = _____ cm
10. 0.250 kg = __________ mg
20. 198 g = _______ kg
30. 120 mg = _____ g
Greater than, less than, or equal to?
31. 63 cm ______ 6 m
34. 536 cm ______ 53.6 dm
32. 5 g ______ 508 mg
35. 43 mg ______ 5 g
33. 1,500 mL ______1.5 L
36. 3.6 m ______ 36 cm
Metric System Challenge
1.
Instrument used to find mass. __ __ __ __ __ __ - __ __ __ __
__ __ __ __ __ __ __
21/23
17
2.
Metric unit for length. __ __ __ __ __
3.
Amount of space an object takes up. __ __ __ __ __ __
4.
The force of this equals 9.8m/s2. __ __ __ __ __ __ __
20
16
10
5.
Metric unit for mass. __ __ __ __
6.
Instrument used to measure metric volume. __ __ __ __ __ __ __ __ __
15
6
7.
__ __ __ __ __ __ __ __
8
25
This equals mass  volume. __ __ __ __ __ __ __
19
24
8.
One meter = 100 of this. __ __ __ __ __ __ __ __ __ __
9.
Metric unit for weight (not mass). __ __ __ __ __ __
4
5
10. Metric unit for liquid volume. __ __ __ __ __
3
11. Amount of matter in an object. __ __ __ __
26
12. Measure of the force of gravity acting on an object. __ __ __ __ __ __
18
13. Metric unit for temperature. __ __ __ __ __ __ __
11
1
14. One liter = 1,000 of this. __ __ __ __ __ __ __ __ __ __ __
7
15. The name of the “bubble.” __ __ __ __ __ __ __ __
22
16. 1,000 grams = one of this. __ __ __ __ __ __ __ __
12
17. Instrument used to measure metric length. __ __ __ __ __ __ __ __ __ __
14
18. One milliliter = one of this. __ __ __ __ __
__ __ __ __ __ __ __ __ __ __
13
19. Width, height, thickness, or distance. __ __ __ __ __ __
9
20. Formula for calculating volume. __ x __ x __
2
Why were the teacher’s eyes crossed?
‘
01
02
03
04
05
06
07
08
09
10
11
12
13
!!
18
19
20
21
22
23
24
25
26
14
15
16
17
Practice Reading a Graduated Cylinder
Each image to the left shows the initial volume of water in a graduated cylinder; each cylinder to the left shows the
new water level after an object has been added. Practice with drawing menisci, finding volume, mass, and density.
***Remember: Read one decimal place to the right of what your smallest increment is.
Example: For the first pair of graduated cylinders, the smallest increment is the “ones” place. Read to the “tenth.”
BEFORE
Mass = 12g
Density =
BEFORE
Mass = 12g
Density =
BEFORE
AFTER
Volume =
AFTER
Volume = 5mL
AFTER
Mass =
Volume = 5mL
Density = 12.45 kg/m3
BEFORE
AFTER
Mass =
Volume =
Density = 5g/mL
BEFORE
AFTER
Mass =
Volume =
Density = 52 kg / m3
BEFORE
AFTER
Mass = 214.5 kg Volume =
Density =
23
Volume and Density
Metric Density:
- Water
Common Volume Conversions:
- Examples
Density Formula:
Will it Float?
- Examples
Practice Problems:
MEASURING MASS, VOLUME, AND DENSITY
To identify unknown solids, scientists often compare the density of the object to densities of known objects. Density
is found by dividing the mass of the object by its volume. In scientific measurement, the base unit of mass is the
___________, and the base unit of volume is the ____________ [remember, we only use metric in science].
Density = Mass / Volume
Find the density of each of the objects given below. Obtain the mass by reading the arms on the triple beam balance,
and the volume by reading the difference between the heights in the graduated cylinders. Reach each to one
decimal point PAST the smallest markings. [hundredths for mass, tenths for volume]
DON’T FORGET TO USE YOUR UNITS!!!
Mass of Object: ________
(Vi) Initial Volume of Water: ______
(Vf) Volume of Water After
Object Was Added _______
Vi = Initial
volume
________
Vf = Final
Volume
Volume of Object =
Vf – Vi = _______________
Density of Object = Mass / Volume
D = ________g_ / ________ml__
Density = ________________
Don’t forget units!!!
****Record Density to the TENTHS
_________
24
Mass of Object: ________
(Vi) Initial Volume of Water: ______
(Vf) Volume of Water After
Object Was Added _______
Vi = Initial
volume
________
Volume of Object =
Vf – Vi = _______________
Density of Object = Mass / Volume
D = ________g_ / ________ml__
Density = ________________
Vf = Final
Volume
Don’t forget units!!!
****Record Density to the TENTHS
_________
Mass of Object: ________
(Vi) Initial Volume of Water: ______
(Vf) Volume of Water After
Object Was Added _______
Volume of Object =
Vf – Vi = _______________
Vi = Initial
volume
________
Density of Object = Mass / Volume
D = ________g_ / ________ml__
Density = ________________
Don’t forget units!!!
Vf = Final
****Record Density to the TENTHS
Volume
_________
Mass of Object: ________
(Vi) Initial Volume of Water: ______
(Vf) Volume of Water After
Object Was Added _______
Volume of Object =
Vf – Vi = _______________
Vi = Initial
volume
________
Density of Object = Mass / Volume
D = ________g_ / ________ml__
Density = ________________
Don’t forget units!!!
Vf = Final
****Record Density to the TENTHS
Volume
_________
25
Name, Date, Hr/Per________________________________________________________________________________
Gummy Bear Lab
adapted from worksheet: T. Trimpe 2002 @ http://sciencespot.net
Part A: Choose one gummy bear from the container on your table. Use the equipment available to measure your
gummy bear and record the data chart. Record all measurements to the tenths [of a centimeter or gram], and
calculations to the nearest hundredth.
a. length = top of head to bottom of feet
d. volume = _______ * _______ * _______
b. width = widest point across the back of the bear
e. density = _______ * _______
c. thickness = front to back at the thickest point
After recording your measurements, answer the following questions on Day 1:
1. Create a hypothesis predicting what will happen to the mass, volume, and density of your gummy bear.
2. Create a hypothesis predicting how your color’s results will compare with those of your classmates.
Part B: Put the bear in a cup labeled with your name and class period. Add 50ml of water to the cup and allow it to
sit overnight. On day 2, remove the gummy bear from the cup of water and use a paper towel to dry it before
making your measurements. Repeat the measurements from Part A and record your data in the correct portion of
the chart. Determine the amount of change for each measurement and record it in the chart.
Data:
Day #
Bear Color
Length
Width
Thickness
Volume
Mass
Density
1
2
Amount
of change
Answer the following questions after completing your calculations:
1. Was your hypothesis regarding the change in your gummy bear correct? Explain, citing your data.
2. Was your hypothesis regarding how your color’s results would compare with those of your classmates?
Explain, comparing actual data.
3. Which change is greater, volume or mass? Explain why.
4. Was there a change in density? Why or why not?
26
Density
DENSITY is a physical property of matter, as each element and compound has a unique
density associated with it. Density defined in a qualitative manner as the measure of the
relative "heaviness" of objects with a constant volume. Density may also refer to how
closely "packed" or "crowded" the particles are of a given material.
Use the formula to answer the problems. You must SHOW your work!
1.
6 mL and 18 g
Density = _____________
2.
18 g and 9 mL
Density = _____________
3.
13 g and 1 cL
Density = _____________
4.
94 g and 4 cL
Density = _____________
5.
94 g and 4 cL
Volume = _____________
6.
4 cL and 8 g
Density = _____________
7.
4 cL and 8 g
Mass = _______________
8.
100 cm3 and 1000 g
Density = _____________
9.
10 g and 10 cm3
Density = _____________
10. 100 g and 20 mL
Density = _____________
11. 100 g and 20 mL
Mass = _______________
12. 100 g and 20 mL
Volume = _____________
13. 88 mg and 32 mL
Mass = _______________
14. 88 mg and 32 mL
Volume = _____________
15. 88 mg and 32 mL
Density = _____________
16. 42 mL and 63 g
Density = _____________
17. 3 mL and 27 g
Density = _____________
18. 27 mL and 39 g
Mass = _______________
19. 65 g/cm3 and 3 mL
Mass = _______________
20. 2 g/cm3 and 1 Liter
Mass = _______________
21. 6 g and 3 mL
Density = _____________
22. 25 g and 5 mL
Density = _____________
23. 36 g and 6 mL
Density = _____________
24. 360 kg and 60 mL
Density = _____________
25. 6 mL and 3 g
Volume = _____________
26. 2 g/cm3 and 6 mL
Density = _____________
27. 8 g/cm3 and 2 g
Volume = _____________
28. 78 g/mL and 6 Liters
Mass = _______________
29. 18 g and 2 g/cm3
Mass = _______________
30. 63 g/cm3 and 7 cm3
Mass = _______________
31. A gold-colored ring has a mass of 18.9 grams and a volume of 1.12 mL. What is the
density? Is the ring pure gold? Pure gold is 19.3 g/mL.
32. What volume would a 0.871 gram sample of air occupy if the density of air is 1.29
g/L?
33. Pumice is volcanic rock that contains many trapped air bubbles. A 225 gram sample occupied 236.6 mL. What is
the density of pumice?
34. The density of water is 1.0 g/mL. Will pumice float on water? Why, or why not?
35. A cup of sugar has a volume of 237 mL. What is the mass of the cup of sugar if the density is 1.59 g/mL?
36. From their density values, decide whether each of the following substances will sink or float when placed in sea
water, which has a density of 1.025 g/mL. Circle those that will float; put a line through those that will sink.
Gasoline 0.66 g/mL
Asphalt l.2 g/mL
Mercury 13.6 g/mL
Cork 0.26 g/ml
Density Word Problems
Use the following formula to answer the problems. You must SHOW your work, CIRCLE your answer, and INCLUDE
appropriate units.
1. What is the density of carbon dioxide gas if 0.196 g occupies a volume of 100 mL?
2. A block of wood 3.0 cm on each side and has a mass of 27 g. What is the density of this block?
3. An irregularly shaped stone was lowered into a graduated cylinder holding a volume of water equal to 2.0
mL. The height of the water rose to 7.0 mL. If the mass of the stone was 25 g, what was its density?
4. A 10.0 cm3 sample of copper has a mass of 89.6 g. What is the density of copper?
5. Silver has a density of 10.5 g/cm3 and gold has a density of 19.3 g/cm3. Which would have a greater mass, 5
cm3 of silver or 5 cm3 of gold?
6. Five mL of ethanol has a mass of 3.9 g and 5.0 mL of benzene has a mass of 4.4 g. Which liquid is more dense?
7. A rock occupies a volume of 20 cm3 and has a mass of 54 g. Find the density of this rock.
8. A sample of iron has the dimensions of 2 cm x 3 cm x 2 cm. If the mass of this rectangular-shaped object is
94 g, what is the density of iron?
9. A rectangular solid of unknown density is 5 meters long, 2 meters high, and 4 meters wide. The mass of this
solid is 300 grams. Given this information for this homogeneous material, calculate the density.
10. A cube made of an unknown material has a height of 9cm. The mass of this cube is 3645 g. Calculate the
density of this cube given this information.
11. A graduated cylinder has 22 mL of water placed in it. An irregularly shaped rock is then placed in the
graduated cylinder and the volume of the rock and water in the graduated cylinder now reads 30 mL. The
mass of the rock is 24 g.
A) What is the volume of the rock?
B) What is the density of the rock?
12. An unknown substance from planet X has a density of 10 g/mL. It occupies a volume of 80 mL. What is the
mass of this unknown substance?
13. A sample of seawater weighs 158 g and has a volume of 156 mL. What is the density?
14. A cylindrical box with a volume of 200 cm3 holds 432 g of sodium chloride. Calculate the density of the salt.
15. What is the mass of ethyl alcohol that fills a 200 mL container? The density of ethyl alcohol is is 0.789 g/mL.
16. A flask that has a mass of 345.8 g is filled with 225 mL of carbon tetrachloride. The mass of the flask and
carbon tetrachloride is found to be 703.55 g. Calculate the density in g/mL and kg/L.
In water, will the item sink or float?
If it SINKS, strike it out. If it FLOATS, (circle) it.
A) Styrofoam (D= 0.5 g/cm3)
F) Alcohol (D= 0.97 g/mL)
K) Tin (D= 7.31 g/mL)
B) Ice (D=0.92 g/cm3)
G) Cork (D= 0.25 g/mL)
L) Aluminum (D= 2.70 g/mL)
C) Bone (D=1.70 g/cm3)
H) Granite (D= 2.70 g/mL)
M) Lead (D= 11.34 g/mL)
D) Balsa wood (D= 0.16 g/cm3)
I) Salt (D= 2.16 g/mL)
N) Iron (D= 7.86 g/mL)
E) Gold (D= 19.32 g/cm3)
J) Sulfur (D= 2.07g/mL)
O) Mercury (D= 13.60 g/mL)
Unit 1 – Lecture 4: Scientific Notation & Significant Figures
Scientific Notation:
- Uses:
- Format:
Changing out of Scientific Notation:
- How?
Significant Figures:
- 5 Rules:
Sig Fig Practice:
Powers of Ten & Scientific Notation
[adapted from information at sparknotes.com & mathgoodies.com]
To make things simpler when expressing very large or small values, scientists express values in terms of "a [times]
10b", where “a” is the coefficient and “b” is number of places the decimal place had to move in order to express “a”
in manageable terms. This type of expression is called scientific notation. Some easy examples of scientific notation
are provided below.
1 = 1x100
10 = 1x101
100 = 1x102
1000 = 1x103
…and so forth…
In the case of numbers smaller than one, the exponent becomes negative, and that negative value represents how
many zeroes there are between the number and the decimal place:
0.1 = 1x10-1
0.01 = 1x10-2
0.001 = 1x10-3
…and so forth…
Express the following powers of ten in "Standard Notation" [ie, 103 = 1000]:
1. 104 =
2. 107 =
3. 1017 =
4. 10-1 =
5. 10-4 =
6. 10-12 =
30
Express the following numbers as powers of ten.
1. 10 =
2. 100,000 =
3. 1,000,000,000,000,000,000 =
4. 0.001 =
5. 1 =
6. 0.000000001 =
Scientific notation is simply a method for expressing, and working with, very large or very small numbers. It is a short
hand method for writing numbers, and an easy method for calculations. Numbers in scientific notation are made up
of three parts: the coefficient, the base [which is always 10] and the exponent. Observe the example below:
5.67 x 105
The exponent must show the number of decimal places that the decimal needs to be moved to change the number
to standard notation. Positive exponents mean that the decimal is moved to the right when changing from scientific
notation back to standard notation; a negative exponent means that the decimal is moved to the left when changing
to standard notation.
Convert the following numbers to "Standard Notation" [ie, 103 = 1000]:
1. 2 x 103 =
3. 9.51 x 1022 =
5. 7.6278 x 10-5 =
2. 2.331 x 105 =
4. 5 x 10-3 =
6. 8 x 10-1
7. The age of earth is approximately 4.5 X 109 years. _________________________ yrs
8. The weight of one atomic mass unit (a.m.u.) is 1.66 x 10-27 kg
______________________________________________________________kg
Convert the following numbers to Scientific Notation:
1. 5,213 =
4. 21,000,000,000 =
7. 0.000314 =
2. 73,200 =
5. 4,713,000,000 =
8. 5,243,670 =
3. 23.21 =
6. 0.02 =
9. 0.00000000043791
10. The human eye blinks an average of 4,200,000 times a year. ______________________________blinks
11. A computer processes a certain command in 15 nanoseconds. (A nanosecond is one billionth of a second.) In
decimal form, this number is 0. 000 000 015 seconds. _________________________________sec
12. There are 60,000 miles (97,000 km) in blood vessels in the human body.
______________________________mi
________________________________km
13. The highest temperature produced in a laboratory was 920,000,000 F (511,000,000 C) at the Tokamak Fusion
Test Reactor in Princeton, NJ, USA.
_____________________________ °F
________________________________°C
14. The mass of a proton is 0. 000 000 000 000 000 000 000 001 673 grams.
__________________________g
15. The mass of the sun is approximately 1,989,000,000,000,000,000,000,000,000,000,000 grams.
______________________g
16. The cosmos contains approximately 50,000,000,000 galaxies. ____________________________galaxies
17. A plant cell is approximately 0. 000 012 76 meters wide. _______________________________m
Find each of the values online or elsewhere. Write each in both Standard and Scientific notation.
18. The distance in km from the Sun to Jupiter.
Standard: ________________________________
Scientific: ____________________________km
19. The distance from the Earth to the moon in km.
Standard: ______________________________km Scientific: ____________________________km
20. The size of an E. coli bacterium [will probably be in micrometers, (μm)]
Standard: ______________________________ μm Scientific: ____________________________ μm
31
Significant Figures
The number of significant figures in the reported value of a quantity is important because it gives an indication of the
precision with which the quantity is known. The more significant figures, the more precise the value. A counted,
rather than measured quantity implicitly contains an infinite number of significant figures (for e.g., 4 apples implies
4.0000000…apples)
What do these numbers imply as to the certainty? Let's see what the number can be distinguished from.
The number 2000 to one significant figure lies between the next numbers above and below:
3
3
1 x 10 = 1000
2 x 10 = 2000
It is a number that lies between 1000 and 3000 -- not very certain, is it.
3
x
10
3
=
3000
The number 2000 to two significant figures lies between:
3
3
1.9 x 10 = 1900
2.0 x 10 = 2000
It is a number that lies between 1900 and 2100 -- more certain than before.
3
2.1 x 10 = 2100
The number 2000 to three significant figures lies between:
3
3
3
1.99 x 10 = 1990
2.00 x 10 = 2000
It is a number that lies between 1990 and 2010 -- more certain, still.
2.01 x 10 = 2010
The number 2000 to four significant figures lies between:
3
3
1.999 x 10
2.000 x 10
It is a number that lies between 1999 and 2001 -- even more certain.
2.001 x 10
3
Rules for Counting Significant Figures
1. Always count nonzero digits
Example: 21 has two significant figures, while 8.926 has four
2. Never count leading zeros [zeros to the left of the first non-zero digit]
Example: 021 and 0.021 both have two significant figures
3. Always count zeros which fall between two nonzero digits
Example: 20.8 has three significant figures; 0.00104009 has six
4. Count trailing zeros if and only if the # contains a decimal point [even if there is nothing after it]
Example: 210 and 210000 both have two significant figures, while 210. has three and 210.00 has five
5. For numbers expressed in scientific notation, ignore the exponent and apply Rules 1-4 to the coefficient
Example: -4.2010 x 1028 has five significant figures
For measured numbers, significant figures relate the certainty of the measurement. As the number of significant
figures increases, the more certain the measurement. The means for obtaining the measurement also becomes more
sophisticated as the number of significant figures increase.
Scientific notation is the most reliable way of expressing a number to a given number of significant figures. In
scientific notation, the power of ten is insignificant. For instance, if one wishes to express the number 2000 to varying
degrees of certainty:
3
2 x 10 is expressed to one significant figure
3
2.0 x 10 is expressed to two significant figures
3
2.00 x 10 is expressed to three significant figures
3
2.000 x 10 is expressed to four significant figures
32
# of
Sig
Figs
# in Scientific
Notation
# of Sig
Figs
1
1.05
17
12300000
2
0.0003040
18
56.340502
3
5.40
19
9.2003498
4
.2 x 103
20
39999999
5
210
21
345.56
6
0.00120
22
4500
7
801.5
23
239.1300
8
0.0102
24
.00004976
9
1,000
25
1.200
10
9.010 x 10-6
26
25.0086
11
101.0100
27
1000000
12
2,370.0
28
1000000.
13
1.00345
29
1200.003
14
.0023087610
30
.0012300
15
1457.
31
1457
16
1.00200
32
.00045321
# in Scientific
Notation
Using two different instruments, I measured the length of my foot to be 27 centimeters and 27.00 centimeters.
Explain the difference between these two measurements – MENTION THE RANGE OF EACH OF THESE NUMBERS [like
how 2 can mean 1-3 or how 2.0 means 1.9-2.1]