AP Chemistry Homework
Chapter 1:
1. Identify each of the following substances as a gas, a liquid, or a solid under ordinary
conditions of temperature and pressure: (a) mercury, (b) sodium bicarbonate (baking
soda), (c) hydrogen, (d) carbon monoxide, (e) oxygen, (f) isopropyl alcohol,
(g) sodium chloride. Ans: L;S;G;G;G;L;S
2. Indicate which of the following are physical processes and which are chemical
processes: (a) corrosion of aluminum metal, (b) cutting a diamond, (c) burning
gasoline, (d) boiling water. Ans: C;P;C;P
3. A match is lit and held under a cold piece of metal. The following observations are
made: (a) The match burns. (b) The metal gets warmer. (c) Water condenses on the
metal. (d) Soot (carbon) is deposited on the metal. Which of these occurrences are
due to physical changes and which are due to chemical changes? Ans: C;P;C;C;
4. In the process of attempting to characterize a substance, a chemist makes the
following observations: The substance is a silvery-white, lustrous metal. It melts at
6490C and boils at 11050C. Its density at 200C is 1.738g/cm3. The substance burns in
air, producing an intense white light. It reacts with chlorine to give a brittle, white
solid. The substance can be pounded into thin sheets or drawn into wires. It is a good
conductor of electricity. Which of these characteristics are physical properties and
which are chemical properties? Ans: chemical – burns to produce white light and
reacts with Cl to produce a white solid
5. Classify the following observations about a substance as either physical or chemical
properties: (a) color, (b) melting point, (c) reactivity with water, (d) boiling point,
(e) state of matter under ordinary conditions, (f) flammability, (g) density,
(h) electrical conductivity, (i) decomposition products upon heating.
Ans: P;P;C;P;P;C;P;P;C
6. Classify the following as a pure substance or a mixture; if a mixture, indicate whether
it is homogeneous or heterogeneous: (a) a chocolate-chip cookie, (b) water, (c) vodka,
(d) a pure gold coin, (e) air, (f) gasoline, (g) iodine crystals, (h) salad dressing.
Ans: hetero;pure;homo;pure;homo;homo;pure;hetero
7. Give the chemical symbol for each of the following elements: (a) carbon, (b) sodium,
( c) iron, (d) phosphorous, (e) potassium, (f) chlorine, (g) nitrogen, (h) silver.
Ans: C;Na;Fe;P;K;Cl;N;Ag
8. Identify the chemical elements represented by the following symbols: (a) He, (b) Mg,
( c) Pb, (d) S, (e) F, (f) Zn, (g) Cu, (h) Ar.
9. In 1807, the English chemist Humphry Davy passed an electric current through
molton potassium hydroxide and isolated a bright, shiny, reactive substance. He
claimed the discovery of a new element, which he named potassium. In those days,
before the advent of modern instruments, what was the basis on which one could claim
that a substance was an element? Ans: characteristic metallic properties similar in
character to sodium (couldn’t be broken down further)
10. A solid white substance A is heated strongly in the absence of air. It decomposes to
form a new white substance B and a gas C. The gas has exactly the same properties
as the product obtained when carbon is burned in an excess of oxygen. What can we
say about whether solids A and B and the gas C are elements or compounds?
Ans: A is a compound; B doesn’t have enough info; C is a compound
11. What basic SI units are appropriate for expressing the following quantities: (a) the
diameter of the earth, (b) the surface area of a tennis ball, (c) the volume of a gasoline
tank, (d) the mass of a brick, (e) the speed of light, (f) the temperature of the air,
(g) square miles, (h) quarts, (i) tons, (j) days, (k) yards, (l) degrees Fahrenheit.
Ans: m; m2; m3; kg; m/s; K; m2; m3; kg; s; m; K
12. What decimal power do the following abbreviations represent: (a) d, (b) c, (c) f,
(d) , (e) M, (f) k, (g) n, (h) m, (i) p?
Ans: 10-1; 10-2; 10-15; 10-6; 106; 103; 10-9; 10-3; 10-12
13. Use appropriate metric prefixes to write the following measurements without the use
of exponents: (a) 3.4 x 10-12m, (b) 4.8 x 10-6mL, (c) 7.23 x 103g, (d) 2.35 x 10-6m3,
(e) 5.8 x 10-9s, 3.45 x 10-3mol.
Ans: pm; nL; kg;cm3; ns; mmol
14. What type of quantity (for example, length, volume, density) do the following units
indicate? (a) L, (b) cm2, (c) mm3, (d) mg/L, (e) ps, (f) nm, (g) K.
Ans: volume; area; volume; density; time; length; temperature
15. Indicate whether the following are measurements of length, area, volume, mass,
density, time, or temperature: (a) 5 ns, (b) 3.2 kg/L, (c) 0.88 pm, (d) 540 km2,
(e) 173 K, (f) 2 mm3, (g) 230C.
Ans: time; density; length; area; temperature; volume; temperature
16. Perform the following conversions: (a) 454 mg to g, (b) 5.0 x 10 –8m to nm,
( c) 0.076mL to L, (d) 1.55 kg/m3 to g/L, (e) 3.05 x 105g to kg, (f) 0.0025m to pm,
(g) 3.45 x 10-8s to ns, (h) 4.5 x 108pm3 to m3.
Ans: 0.454 g; 5.0 x 10-17nm; 7.6 x 10-5L; 1.55 g/L; 305 kg; 2.5 x 103 pm; 34.5 ns;
4.5 x 10-28 m3
17. (a) A sample of chloroform, a liquid once used as an anesthetic, has a mass of
37.25 g and a volume of 25.0 mL. What is its density? (b) The density of platinum
23.4 g/cm3. Calculate the mass of 50.0 cm3 of platinum. ( c) The density of
magnesium is 1.74 g/cm3. What is the volume of 175 g of this metal? (d) A cube of
plastic 1.2 x 10-5 km on a side has a mass of 1.1 g. What is the density in g/cm3?
Will this material float on water? (e) The density of liquid bromine is 3.12 g/mL.
What is the mass of 0.500 L of bromine? (f) The density of a piece of ebony wood is
1.20 g/cm3. What is the volume of 8.74 kg of this wood?
Ans: 1.49 g/mL; 1170 g; 101 cm3; 6.4 x 10-1g/cm3(floats); 1560 g; 7280 cm3
18. Make the following temperature conversions: (a) 680F to 0C, (b) –36.70C to 0F,
( c) –150C to K, (d) 415 K to 0F, (e) 15000F to K, (f) 920F to 0C, (g) 8040C to K,
(h) 234.28 K to 0F.
Ans: 200C; -34.10F; 258 K; 2880F; 1088.6 K = 1100 K; 330C; 1080 K; -37.70F
19. Indicate which of the following are exact numbers: (a) the number of inches in a
mile, (b) the diameter of a dime, (c) the mass of a 12 oz bag of potato chips, (d) the
number of ounces in a pound, (e) the number of micrometers in a kilometer, (f) the
number of inches in a kilometer, (g) the mass of a Nerf ball, (h) the number of seconds
in a year, (i) the surface area of a penny, (j) the temperature of the surface of the sun,
(k) the number of mL in a cubic foot of water, (l) the number of pages in this book.
Ans: Exact are a, d, e, f, h, k, l
20. What is the number of significant figures in each of the following measured
quantities? (a) 122g; (b) 0.002796 s; (c) 8.07 mm; (d) 0.01050 L; (e) 5.7750 X 10-4
cm3, (f) 3.141 cm; (g) 0.000050 m2; (h) 3,480,200 s; (i) –1.200oC; (j) 1.0800 X
10-2 L. Ans: 3; 4; 3; 4; 5; 4; 2; 5; 4; 5
21. Round each of the following numbers to four significant figures: (a) 12,345,670; (b)
2.35500; (c) 456,500; (d) 3.218 X 103; (e) 0.000657030; (f) 100,500.1.
Ans: 12,350,000; 2.355; 456,500; 3.218 x103; 0.0006570; 1.005 x 105
22. Round each of the following numbers to three significant figures: (a) 10.000; (b)
0.05000; (c) 23,000; (d) 1.565 X 101; (e) 9,834.05; (f) –1235.
Ans: 10.0; 0.0500; 2.30 x 104; 1.57 x 101; 9.83 x 103; -1240
23. Carry out the following operations and express the answers with the appropriate
number of significant figures: (a) 1.23056 + 67.809; (b) 23.67 – 500; (c) 890.05 X
12.3; (d) 88, 132/22.500; (e) 324 – (6104.5/22.3); (f) [(285.3 X 106) – (12.000 X 103)];
(g) (0.0045 X 30,000.0) + (283 X 12); (h) 869 X [1255- (3.45 X 103)].
Ans: 69.040; -476; 1.09 x 104; 3917.0; 50; 2.853 x 108; 3536; -1.91 x 106
24. Perform the following conversions: (a) 3.60 mi to m; (b) 2.00 days to s; (c) $1.95/gal
to dollars per liter; (d) 5.0 pm/us to m/s; (e) 85.00 mi/hr to m/s; (f) 33.35 ft3 to cm3.
(g) 7.5 ft to cm; (h) 4.45 qt to mL; (i) 35.7 in/hr to mm/s; (j) 2.00 yd3 to m3; (k) $3.99
per pound to pennies per gram. Ans: 5.79 x 103m; 1.73 x 105g; $0.515/L; 5.0 x 10-6
m/s; 38.00 m/s; 9.444 x 105 cm3; 2.3 x 102 cm; 4.21 x 103mL; 0.252 mm/s; 1.53 m3;
$0.880/g
25. (a) If the gasoline tank of a compact car has a capacity of 12 U.S. gal, what is its
capacity in liters? (b) If a bee flies at an average speed of 3.4 m/s, what is its average
speed in mi/hr? (c) What is the engine piston displacement in liters of an engine whose
displacement is listed as 320 in3? (d) How many liters of wine can be held in a wine
barrel whose capacity is 31 gal? (e) The recommended adult dose of Elixophyllin a
drug used to treat asthma, is 6 mg/kg of body mass. Calculate the dose in milligrams
for a 170-lb person. (f) If an automobile is able to travel 244 mi on 11.2 gal of
gasoline, what is the gas mileage in km/L?
Ans: 45 L; 7.6 mi/hr; 5.24 L; 1.2 x 102 L; 500 mg; 9.26 km/L
26. The density of air at ordinary atmospheric pressure and 25oC is 1.19 g/L. What is the
mass, in kilograms, of the air in a room that measures 8.2 X 13.5 X 2.75 m?
Ans: 3.6 x 102kg
27. The maximum allowable concentration of carbon monoxide in urban air is 10 mg/m3
over an 8-hr period. At this level, what mass of carbon monoxide is present in a room
measuring 8 X 12 X 20 ft? Ans: 0.54 g or 540 mg
28. Mercury is traded by the “flask,” a unit that has a mass of 34.5 kg. What is the
volume of a flask of mercury if the density of mercury is 13.6 g/mL?
Ans: 2.54 L
29. The Morgan silver dollar has a mass of 26.73 g. By law, it was required to contain
90 percent silver, with the remainder being copper. (a) When the coin was minted in
the late 1800s, silver was worth $1.18 per troy ounce (31.1 g). At this price, what is
the value of the silver in the silver dollar? (b) Today, silver sells for $3.70 per troy
ounce. How many silver dollars are required to obtain $25.00 of pure silver.
Ans: $1.00; 8 coins
30. In March 1989, the Exxon Valdez ran aground and spilled 240,000 gallons of crude
petroleum off the coast of Alaska. One barrel of petroleum is equal to 42 gal. How
many milliliters of petroleum were spilled? Ans: 3.8 x 1010 L
31. A pound of coffee beans yields 50 cups of coffee (4 cups = 1 qt). How many
milliliters of coffee can be obtained from 1 g of coffee beans? Ans: 30 mL
32. Which of the following are intensive properties: (a) mass; (b) density;
(c) temperature; (d) area; (e) color; (f) volume. Ans: b, c, e
33. (a) What is the difference between a hypothesis and a theory? (b) What is the
difference between a theory and a scientific law? Which addresses how matter
behaves, and which addresses why it behaves that way?
34. A sample of ascorbic acid (vitamin C) is synthesized in the laboratory. It contains
1.50g of carbon and 2.00g of oxygen. Another sample of ascorbic acid isolated from
citrus fruits contains 6.35g of carbon. How many grams of oxygen does it contain?
Which law does this illustrate? Ans: 8.47 g oxygen; Law of Definite Proportions
35. Give the derived SI units for each of the following quantities in terms of base SI
units: (a) acceleration = distance/time2; (b) force = mass X acceleration; (c) work =
force X distance; (d) pressure = force/area; (e) power = work/time.
36. Magnesium is used in automobile wheels because it is “lighter” than steel. What is
a more scientifically correct statement of this? Ans: less dense
37. Is the use of significant figures in each of the following statements appropriate?
Why or why not? (a) The 1976 circulation of Reader’s Digest was 17,887,299.
(b) There are more than 1.4 million people in the United States who have the surname
Brown. (c) The average annual rainfall in San Diego, California, is 20.54 in. (d) The
Population of East Lansing, Michigan, was 51,237 in 1979.
Ans: a, b, d are no (counting); c is yes (measured)
38. The annual production of sodium hydroxide in the United States in 1991 was 24.39
billion pounds. (a) How many grams of sodium hydroxide were produced in that year?
(b) The density of sodium hydroxide is 2.130g/cm3. How many cubic kilometers were
produced? Ans: 1.106 x 1013 g; 5.194 x 10-3 km3
39. You are given a bottle that contains 2.36 mL of a yellow liquid. The total mass of
the bottle and the liquid is 5.26g. The empty bottle weighs 3.01g. What is the density
of the liquid? Ans: 0.953 g/mL
40. An 8.47-g sample of a solid is placed in a 25.00-mL flask. The remaining volume in
the flask is filled with benzene in which the solid is insoluble. The solid and the
benzene together weigh 24.54g. The density of the benzene is 0.879g/mL. What is the
density of the solid? Ans: 1.26 g/mL
41. The U.S. quarter has a mass of 5.67g and is approximately 1.55mm thick. (a) How
many quarters would have to be stacked to reach 575ft, the height of the Washington
Monument? (b) How much would this stack weigh? (c) How much money would this
stack contain? (d) At this writing, the national debt is $4.2 trillion. How many stacks
like the one described would be necessary to pay off this debt?
Ans: 1.13 x 105 quarters; 641 kg; $28,267.75; 148579 stacks
42. A piece of aluminum foil measuring 12.0 in. by 15.5 in. has a mass of 5.175g.
Aluminum has a density of 2.70g/cm3. What is the thickness of the foil in millimeters?
Ans: 1.60 x 10-2 mm
43. A cylindrical glass tube 15.0cm in length is filled with ethanol. The mass of ethanol
needed to fill the tube is found to be 9.64g. Calculate the inner diameter of the tube in
centimeters. The density of ethanol is 0.789g/mL.
44. Chromatography is a simple but reliable method for separating a mixture into its
constituent substances. Suppose you are using chromatography to separate a mixture
of two substances. How would you know whether the separation is successful? Can
you propose a means of quantifying how good or how poor the separation is?
45. Suppose you are given a sample of a homogeneous liquid. What would you do to
determine whether it is a solution or a pure substance? Ans: Check density
46. The distance from Earth to the moon is approximately 240,000mi. (a) What is the
distance in millimeters. (b) The Concorde SST has an airspeed of about 2400km/hr. If
the Concorde could fly to the moon, how many mega-seconds would it take?
Ans: 3.9 x 1011 mm; 0.58 Ms