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HONORS CHEMISTRY
MS. SONDERLEITER
Source: http://www.siraze.net/chemistry/sezennur/subjects/comics/comics22.htm
UNIT 1 – BASIC SKILLS (Measurement & Units, Lab Equipment & Skills, Significant Figures, Density,
Scientific Notation, Matter, Energy)
Name:__________________________________________
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Lesson 0 – Background Skills
Students MUST be able to
• Define the measured quantities of mass, length, area, perimeter, volume, time,
temperature, and energy.
• Choose the appropriate units for each measurement.
• Explain the basis of different measuring systems and discuss the benefits of the
metric system in science.
• Memorize the metric prefixes, their symbols, and their corresponding meanings.
• Use dimensional analysis to covert between units.
• Perform conversions within the metric system using memorized conversion
factors and between English and metric units using provided conversion factors.
• Write numbers in scientific notation.
• Convert numbers from scientific notation to standard notation.
Category Definition Measurement Tool Units
Mass
Length
Height
Width
Perimeter
Area
Volume
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Time
Temperature
Energy
Units in Everyday Life: We use units every day, often without even realizing it. In the
statements that follow, you will find a wide variety of interesting facts, but each is
missing a crucial piece of information – the dimensions (units)! All the statements are
meaningless until you supply the appropriate units. On the basis of your experiences, try
to match the appropriate units for the list provided.
carats
cm
degrees Celsius
degrees
Fahrenheit
feet
grams/mL
inches
kcal (Cal)
kilograms
kilometers
liters
miles
miles per hour
milligrams
pounds
stories
tons
yards
1) America’s tallest building (Sears Tower in Chicago) is 110 __________high.
2) The Empire State Building in New York is 1250 _______________high.
3) The Nile is the world’s longest river. It is 4180 ______________long.
4) The Amazon River in South America is 6296 _______________long.
5) The coldest temperature ever recorded was -128.6 ___________ in Vostok,
Antarctica, in 1983.
6) The highest recorded temperature in the United States was in Death Valley,
California, when the mercury reached 57____________.
7) The world record rainfall occurred in Cherrapunji, India, where 1042
____________ of rain fell in one year.
8) The largest recorded hailstone to ever fall landed in Coffeyville, Kansas, in 1979.
It had a diameter of 44.5 ________!
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9) The longest punt in NFL history was by Steve O’Neal of the New York Jets. He
kicked the football 98 ____________.
10) The largest seed in the world is that of the coc-de-mer coconut tree, which may
weigh as much as 40 _____________!
11) The world’s largest meteorite is located in Southwest Africa. It weighs 650
_________.
12) The most popular soft drink in the world is currently Coca Cola. More than 210
million ____________were consumed each day in 1990.
13) The largest diamond in the world was mined from South Africa in 1905 and
weighs 3106 ____________.
14) Earth is the densest of the nine planets, with an average density of 5.515
___________.
15) The world’s fastest aircraft is the Lockheed SR-71 Blackbird, clocking a record
speed of 2,193.67 ________________.
16) The largest gold nugget ever found has a mass of 100 _____________!
17) One large chicken egg contains an average of 274 _____________ of cholesterol.
18) A 16-year old male requires an average of 2800 ____________ of energy per day
while and average 16-year old female requires only 2100 ______________.
Concluding Questions/Main Points:
1) Why is it essential that appropriate units accompany all measurements?
2) Individuals who travel to regions of the world with poor sanitation are warned to
filter or boil their water before drinking it to remove deadly water-born pathogens
that cause diseases such as cholera and typhoid. If you were traveling in a region
known to have a polluted water supply, would you drink water that your host said
had been heated to 100 degrees for five minutes? Explain?
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English System Metric System
Description
Pros
Cons
1) Which system of units will we use in chemistry? Why?
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Metric Prefixes and Powers
Prefix Symbol Power
of 10
Meaning Decimal Notation Example
(mass)
109
106
103
10-2
10-3
10-6
10-9
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Perform the following unit conversions.
1) 11.7 mm to m
2) 0.9 cg to g
3) 44 nm to m
4) 4.53 kg to g
5) 9,350 µs to s
6) 0.0014 Gm to m
7) 76 mL to µL
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8) 0.450 Mm to cm
9) 0.089 kg to mg
10) 150.0 lbs to kg
11) 12,850 ft to miles
12) 48,987 min to hr
13) 18 in to cm
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14) 6.0 gal to mL
15) 56,098 min to days
16) 3.2 tons to grams
Additional Practice:
• http://chemistry.about.com/od/convertcalculate/a/conversions.htm
• http://proton.csudh.edu/homeworkcs/hwconvertvolcsn7.html
• http://proton.csudh.edu/homeworkcs/hwconvertmasscsn7.html
• http://proton.csudh.edu/homeworkcs/hwconvertlengthcsn7.html
Standard Notation Scientific Notation
8,700,000
3.4 x 10-3
0.00098
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Lesson 1 – Introduction to the Laboratory
Students will be able to
• Name and locate standard lab equipment and describe its use.
• Explain and identify the standard lab safety rules and procedures.
Equipment Name What do you think it is used for?
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Picture reference: Laboratory Equipment. Created by the Chemistry Faculty and the Media Center at Santa Monica College. 8/30/2005 <http://homepage.smc.edu/chem10/Equipment.html>
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Archer School for Girls
Science Safety Agreement
You are enrolled in a laboratory science course. Experiments are part of the foundation
of scientific knowledge. A laboratory should be a safe place to work and learn. The
experiments you will be conducting throughout the year have been selected, in part,
because of their ability to be done safely. Your teacher will go over the following rules
and guidelines for the lab. You will be given the opportunity to ask questions about these
rules. After your teacher has discussed these rules, you and your parents will sign a copy
of this agreement to be kept by your teacher.
1. Perform all experiments as directed. Never make substitutions or changes to a
procedure without first consulting your teacher.
2. Be properly prepared for each experiment. Be sure to read and complete the pre-
lab and know the hazards before you do the experiment.
3. Wear the appropriate protective equipment. Always wear safety goggles in the
lab when chemicals are being used – no exceptions!
4. Know the locations and uses of the safety devices in the lab. This includes the
shower, eye wash, fire extinguisher, sinks, and first aid kit.
5. Act in a responsible manner at all times. No running or horseplay in the lab.
6. Wear closed-toed shoes in the lab.
7. Tie back your hair if it is long, and refrain from wearing large jewelry.
8. Never taste a chemical, even if it is a substance found in households.
9. No food or drink is permitted in the lab at any time.
10. Turn off a Bunsen burner or heat source whenever you are not using it. Never
operate a heating source unattended.
11. Read chemical labels carefully. Know what you are using!
12. Never touch chemicals unless directed.
13. When checking for chemical odor – waft, don’t sniff the chemical.
14. Report all accidents, inures, or near misses to your teacher immediately, no matter
how small. (This includes cuts, burns, acid spills, etc.)
15. Dispose of chemicals properly. Your teacher will inform you of proper waste
disposal at the beginning of each experiment.
16. Do not use more material in a lab than is required, and never return unused
reagent back to the reagent bottle.
17. Clean up spills immediately. (This includes water.) Keep your lab area neat and
free of clutter.
18. Never take chemicals out of the laboratory.
19. Wash your hands with soap and water at the end of each experiment.
20. Allow plenty of time for hot glass to cool. Remember: hot glass looks like cool
glass!
21. Always use common sense and good judgment in the lab.
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* It is NOT recommended that contact lenses be worn in the lab. The permeability of
the lenses allows chemicals to enter the eye and can cause irritation. If you choose to
wear contact lenses, please indicate this at the bottom of the page.
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
I, ________________________, have read, understand, and agree to follow these science
safety rules and procedures. I agree to abide by any additional instructions, written or
verbal, provided by my science teacher during an experiment.
Student Signature ___________________________________ Date __________
Parent Signature ____________________________________ Date __________
I wear contact lenses: Yes _______ No_______
Please list any allergies below:
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Lesson 2 – Measurement & Uncertainty
Students will be able to
• Explain why scientists must have a common system for performing
measurements.
• Report measurements with the appropriate number of digits using the rules of
significant figures.
Measure the length of the leaf below.
Source: http://cyberbridge.mcb.harvard.edu/math_2.html
Significant Figures Rule for Measurement in Science:
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1) Read the material provided at each station.
2) Get teacher signature for proper equipment use.
3) Fill out worksheet.
Station 1: Triple Beam Balance
Sample Mass of Beaker Mass of Beaker and
Sample
Mass of Sample
Itself
Sample #1
Sample #2
What is the smallest graduation (place value) on the triple beam balance?
What digit/place value do you have to estimate?
Station 2: Electronic Balance
Sample Mass of Sample Itself
Sample #1
Sample #2
Sample #3
Sample #4
What makes a top-loading balance easier to use than a triple beam balance?
What is the smallest graduation (place value) on the top-loading balance?
What digit (place value) do you have to estimate?
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Station 3: Beaker
Sample Color Volume
Beaker #1
Beaker #2
Beaker #3
Beaker #4
What is the smallest graduation (place value) on each of the 4 different beakers that you
used?
Beaker #1 ___________ Beaker #3_______________
Beaker #2 ___________ Beaker #4_______________
What digits (place value) do you have to estimate on each beaker?
Beaker #1 ___________ Beaker #3_______________
Beaker #2 ___________ Beaker #4_______________
Which beaker gives the most accurate measurement? Why?
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Station 4: Graduated Cylinder
Sample Color Volume
Cylinder #1
Cylinder #2
Cylinder #3
Cylinder #4
What is the smallest graduation (place value) of each of the cylinders used?
Cylinder #1 ___________ Cylinder #3_______________
Cylinder #2 ___________ Cylinder #4_______________
What digit (place value) do you have to estimate on each of the cylinders?
Cylinder #1 ___________ Cylinder #3_______________
Cylinder #2 ___________ Cylinder #4_______________
Conclusion Questions/Main Points:
1) What determines the accuracy of a measuring device?
2) How do scientists reflect the accuracy of their equipment when reporting a
measurement?
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Lesson 3 – Significant Figures
Students will be able to
• Explain the importance of significant figures.
• Count significant figures.
• Perform calculations and write answers with the proper significant figures.
What are significant figures?
Rules for Counting Significant Figures
How many significant figures are in each of the following numbers?
1. 3.000010
2. 98,001,000
3. 0.00107
4. 85,000.
5. 709
6. 0.007
7. 600
8. 9.000
9. 6.530
10. 9.007
Additional Practice:
• http://proton.csudh.edu/homeworkcs/hwsigfigurescsn7.html
• http://science.widener.edu/svb/tutorial/sigfigures.html
• http://www.lon-capa.org/~mmp/applist/sigfig/sig.htm
• http://www.dallassd.com/our%20schools/high%20School/Chemsite/hotpot/sf.htm
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Lesson 4 – Significant Figures & Calculations
Students will be able to
• Count significant figures.
• Perform calculations and write answers with the proper significant figures.
Why?
Addition & Subtraction Rules
Practice:
1) 149.7 + 23.55 + 2000.34 =
2) 1.0322 x 103 + 4.34 x 10
3 =
3) 95.3 – 12.678 =
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Multiplication & Division Rules
Practice:
1) (0.0432)(2.909) (4.43 x 108) =
2) (8.507) / (0.0004) =
Mixed Math (Ahhhhhhhhhh!)
Practice:
1) 7.33(45.6 – 5.09) =
2) (0.8922) / [(0.00932)(4.03 x 102) =
Additional Practice:
• http://www.teacherbridge.org/public/bhs/teachers/Dana/SigFigOperations.html
• http://www.aaaknow.com/g71f_nx1.htm
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Significant? . . . . I Don’t Think So
By Michael Offutt, 1997, Chemistry Songbag II
You know, I really love my calculator,
When I multiply, divide, subtract or add.
I get so many digits in my answer.
Lots and lots of digits can’t be bad . . . right?
Well, my science teacher told me to be careful,
Some of those digits have to go,
She said I have to learn to round my answer.
There are rules that science students have to know.
This calculator is my special friend,
Its little brain never makes mistakes,
Every number on its screen is mathematically correct,
But significant? . . . I don’t think so.
Every scientific measurement’s uncertain,
Uncertain to varying degrees.
So when one or more are used in calculations,
The answer also has uncertainty.
When you multiply or divide uncertain values,
Your answer should be rounded when you’re through.
To the least number of sig figs in any of those values.
It’s really, really not that hard to do.
When you add or subtract uncertain values,
Decimal places are the key.
Count the fewest number of decimal places in those values.
And then you should round accordingly.
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Lesson 5 – Matter
Students will be able to
• Define matter.
• Differentiate (verbally and with molecular level drawings) between the different
forms of matter (atoms, molecules, compounds, elements, pure substances,
mixtures, homogeneous mixtures, heterogeneous mixtures).
What is matter?
Sort the following into three categories: matter, not matter, or not sure.
peanut butter
water
fish
light
garbage
time
motion
the human brain
carbon dioxide
air
yourself
energy
an idea
heat
tree
energy
Pieces of Matter
Atoms Molecules
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BUT atoms and molecules are VERY small. We can’t see just 1!
Source: http://wps.prenhall.com/wps/media/objects/165/169061/GIFS/AAAUASO0.JPG
Molecular Level Drawings . . .
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Procedure: Examine the contents of the nine petri dishes that are set up in the lab.
Petri
Dish
#
Contents are either (choose one)
a pure substance or a mixture
Contents contain: element,
compound, or mixture
Atoms,
molecules, or both are present
1
2
3
4
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Petri
Dish
#
Contents are either (choose
one) a pure substance or a
mixture
Contents contain: element,
compound, or mixture
Atoms,
molecules, or both are present
5
6
7
8
9
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Lesson 6 – States of Matter & Drawings
Students will be able to
• Describe the different states of matter in relation to molecular motion and
position.
• Identify a type of matter based on a molecular level drawing.
• Create a molecular level drawing to represent a specific type of matter.
Source: http://www.suntrek.org/images/states.gif
ANIMATION
Solid Liquid Gas Plasma
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Phase Changes
Source: http://www.gcsescience.com/Interconverting-Solid-Liquid-Gas.gif
Molecular Level Drawings
1) Draw molecular level diagrams to show the difference between a mixture and a
pure substance.
2) Draw molecular level diagrams to show the difference between a compound and a
mixture.
3) Draw molecular level diagrams to show the difference between a homogeneous
mixture and a heterogeneous mixture.
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Source: http://intro.chem.okstate.edu/HTML/SCFIMG/SCH111.gif
1) Which are solids? Liquids? Gases?
2) Which are mixtures and which are pure substances?
3) Which are atoms? Molecules?
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Lesson 7 – Physical Properties of Matter
Students will be able to
• Define and give examples of physical properties of matter.
What is a physical property?
Physical Properties:
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Lesson 8 – Density
Students will be able to
• Define and calculate the density of solids, liquids, and gases.
• Describe how to determine the density of various substances experimentally.
• Determine whether a substance will sink or float in water.
• Explain why the density of a substance is independent of the amount of the
substance present.
What is density? What does it mean when you say something is dense?
Finding Density in the Lab
Measuring Mass Measuring Volume
Solid
Triple Beam Balance Gizmo
Geometric Solid
Irregular Solid
Liquid
Gas
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Calculations
1) Given the following mass, volume, and density information, calculate the missing
quantity.
a. mass = ? ; volume = 124.1 mL; density = 0.821 g/mL
b. mass = 0.721 lbs; volume = 241 cm3; density = ?
2) A cube of metal weighs 1.45 kg and displaces 542 mL of water when immersed.
Calculate the density of the metal.
3) If 5.67 g of silver, which has a density of 10.5 g/cm3, is dropped into a graduated
cylinder containing 34.5 mL of water, to what volume will the water level rise?
4) You find a gold nugget that has a mass of 253.36g and a density of 19.3 g/mL.
a. What volume of gold do you have?
b. If it takes 1.32 mL of gold to make 1 ring, how many rings can you make?
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5) You find a mystery tube of gas that has a volume of 3.54 mL and a mass of
0.0063g. What is the density and identity of the gas?
Gas Density (g/mL)
Ar 0.001784
He 0.0001785
N2 0.001250
O2 0.001429
6) For a material to float on the surface of water, the material must have a density
less than that of water (1.0 g/mL) and must not react with the water or dissolve in
it. A spherical ball has a radius of 0.50 cm and weighs 2.0 g. Will this ball float or
sink when placed in water? (Hint: the volume of a sphere = (4/3)πr3)
7) The density of air at ordinary atmospheric pressure and 25°C is 1.19 x 10-3
g/mL.
What is the mass, in kilograms, of the air in a room that measures 12.5 x 15.5 x 20
ft?
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Lesson 9 – Separating Mixtures
Students will be able to
• Describe how to separate simple mixtures.
• Define and describe the scientific reasoning behind the processes of filtration and
distillation.
Heterogeneous Mixtures
Mixture Composition How to separate . . .
Rocks and Water
Sand and Water
Homogeneous Mixtures
Mixture Composition How to separate . . .
Salt and Water
Rubbing Alcohol and Water
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Filtration
Distillation
Extraction
Coming Later On (Chromatography)
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Lesson 10 – Energy
Students will be able to
• Define energy.
• Differentiate between energy and temperature.
• Explain and give examples of the law of conservation of energy.
• Convert between Celsius, Fahrenheit, and Kelvin temperature scales.
What is energy?
What are some of the different types of energy?
Key Terms:
• Energy Transfer –
• Law of Conservation of Energy –
• Heat –
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• Endothermic –
• Exothermic –
• Temperature –
Temperature Conversions:
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Lesson 11 – Energy Transfer & Specific Heat
Students will be able to
• Define specific heat.
• Calculate energy changes, final and initial temperatures, or specific heat using the
equation q = mc∆T.
Heat Transfer:
Specific Heat:
Source:
http://www.explorelearning.com/ELContent/gizmos/ELScience_Deliverable/ExplorationGuides/images/EL_MSPS_Calorie2.gif
Relationship Between Energy Transfer, Temperature, and Specific Heat:
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Practice:
1. Calculate the specific heat of a substance if a 35 g sample absorbs 48 J as the
temperature is raised from 293 K to 313 K.
2. The temperature of a piece of metal with a mass of 95.4 g increases from 298.0 K
to 321.1 K when the metal absorbs 849 J of energy as heat. What is the specific
heat of the metal? Using the chart above, determine the identity of the metal.
3. If 980 kJ of energy is transferred to 6.2 L of water at 291 K, what will the final
temperature of the water be?
4. How much energy as heat must be transferred to raise the temperature of a 55 g
sample of aluminum from 22.4 °C to 94.6 °C? The specific heat of aluminum is
0.897 J/g°C.