Chemistry Unit 1 Test Items
Vocabulary:
Science, chemistry, analytical chemistry, inorganic chemistry, organic chemistry, physical chemistry, theoretical
chemistry, biochemistry, nuclear chemistry, scientific method, hypothesis, experiment, theory, law, principle, accuracy, precision,
accepted value, experimental value, error, % error, significant figures, scientific notation, conversion factor, dimensional analysis,
kinetic theory, kinetic energy, pressure, vacuum, barometer, manometer, vapor, vaporization, vapor pressure, boiling point, normal
boiling point, melting point, normal melting point, crystal, amorphous solid, phase diagram, sublimation, triple point.
Concepts & Skills:
List and explain the 5 steps of the scientific method. Compare and contrast hypothesis, law/principle, and
theory. Know the 7 branches of chemistry and relate situations to a particular branch of chemistry. Identify the SI base units, and
identify the primary SI derived units used in Chemistry (L, J, Pa, m3, m2, g/mL & g/cm3. Know the special relationship for volume
units; 1 mL = 1 cm3. Evaluate the difference between an SI base unit and an SI derived unit. Compare and contrast qualitative
measurements and quantitative measurements. Compare and contrast accuracy and precision. Identify differences and similarities
between the metric and SI systems of measurement. Convert SI units using the factor label method. Memorize the name, symbol, and
value of the main SI prefixes. Convert SI units and USCS units using the factor label method. Convert temperature units using
established conversion equations. Convert complex units of measure using dimensional analysis. Write numbers into scientific
notation from standard Arabic numbers. Write numbers as standard Arabic numbers from scientific notation numbers. Identify the
number of significant digits in a measured value. Round results of calculations of measured values to their proper number of sig figs.
Calculate the error of a measurement. Calculate the % error of a measurement. Perform calculations involving density. Explain the
kinetic theory of matter. Use kinetic theory to explain the following: gas particle movement, gas pressure, particle relationships in
gases, liquids, and solids. Convert between the units of pressure; atm, kPa, and mm Hg.
Study Problems:
Chapter 1: p. 25-26, # 16, 18, 23-37.
Chapter 3: p. 78-80, # 36-61, 64-78.
Chapter 4: p. 103-104, #33-50, 52-58, 62-63, 65-66.
Chapter 10: p. 289-291, #20-26, 29-42, 44, 46-54, 56, 58, 60-61, 70-73.
Chemistry Unit 1 Study Problem Answers
Chapter 1:
16. Chemistry is the study of matter and the changes that matter undergoes. Matter is the stuff material things are made of.
18. a) 4 b) 3 c) 1 d) 5 e) 2
23. Experiments are used to test hypotheses.
24. Various Answers Acceptable, ex. Troubleshooting an electronic device; Conquering a video game
25. If you are sure that your experiment is not flawed in any way, then you must develop a new hypothesis.
26. c.
27. A language uses its vocabulary to express thoughts about all things. The vocabulary of the sciences is used to express concepts
and facts about the workings of nature.
28. b.
29. Diagram should have string a and c connected as parts of one string; a and c are the ends of the string sticking out the holes. One
end of string b is sticking out of hole b, and the rest of the string is inside the box.
30. The doctor’s hypothesis is that you have a strep throat. She tests the hypothesis with an experiment to learn whether your throat is
infected with strip bacteria.
31. The experiment may be flawed; if not, the results are evidence that the theory needs to be revised.
32. In general, the more you know, the better off you are. The study of chemistry helps you think logically and analytically. This is a
very useful skill in any career.
33. a) 1 b) 3 c) 1
34. A hypothesis is retained if it is supported by the results of the experiments; otherwise it is rejected and you must form a new
hypothesis.
35. No; for any discovery to take place, the discoverer must have the knowledge to recognize the significance of the observation or
data.
36. A theory can never be proven. Although a theory may be strongly supported by existing experiments, data, and observations,
there is always the possibility that a new kind of experimental result will show the theory to be false.
37. a) The textbook contains all of the major content and concepts covered in the course. The visuals, reading/studying guides, and
practice/review features are essential elements in learning and understanding chemistry. b) (false statement) Chemistry concepts are
interwoven and are best understood as parts of a big picture. Seeing connections and building a framework imply understanding and
comprehension, not just memorization.
Chapter 3:
36. a) qualitative b) quantitative c) qualitative d) quantitative
37. a) precision b) accuracy c) precision d) precision e) accuracy f) accuracy
38. when using an improperly calibrated measuring device.
39. Lissa) inaccurate and imprecise. Lamont) accurate and precise. Leigh Anne) inaccurate but precise
40. a) accurate and precise
b) inaccurate but precise
c) inaccurate and imprecise
41. a) infinite b) infinite c) infinite d) 4 e) infinite f) 3
42. a) 98.5 L b) 0.000 763 cg c) 57.0 m d) 12.2 °C e) 0.00750 × 10 ‒4 mm f) 1,760 mL
43. a) 9.85 × 101 L b) 7.63 × 10‒4 cg c) 5.70 × 101 m d) 1.22 × 101 °C e) 7.50 × 10 ‒7 mm f) 1.76 × 103 mL
44. a) 43 g b) 7.3 cm2 c) 225.8 L
d) 92.0 kg e) 32.4 m3 f) 104 m3
45. a) 4.3 × 101 g b) 7.3 × 100 cm2 c) 2.258 × 102 L d) 9.20 × 101 kg e) 3.24 × 101 m3 f) 1.04 × 102 m3
46. The error is the difference between the accepted and the experimental values. The percent error is the absolute value of the error
divided by the accepted value multiplied by 100%.
47. The absolute value of the error is used, so you always will have a positive value.
48. 4%
49. 23.9 g
50. Ex. Units are used by scientists and nations everywhere. Prefix measurements are based on powers of 10. Prefixes have the
same meaning when attached to different units.
51. a) second, s
b) meter, m
c) kelvin, K
d) kilogram, kg
52. h) picometer = 10‒12 m, f) nanometer = 10‒9 m, b) micrometer = 10‒6 m, d) millimeter = 10‒3 m, a) centimeter = 10‒2 m, g)
decimeter = 10‒1 m, c) kilometer = 103 m
53. a) 2.4 mm b) 17.6 cm
c) 27.6 cm or 2.8 dm
54. Volume is length unit cubed because of the volume equation: V = l × w × h.
55. 7.9 × 102 cm3.
56. a) 2 b) 3 c) 1 d) 4
57. a) 0.01 g b) 0.000 001 g c) 1,000 g d) 0.001 g
58. The mass of an object is constant. The weight of an object varies with location because the pull of gravity on a mass is different
at different locations.
59. a) 1 b) 4 c) 2 d) 3
60. Yes, neither mass nor volume changes with location.
61. No; the density of the metal bar is 12 g/cm3, and the density of gold is 19 g/cm3, therefore the metal bar cannot be gold.
64. The carbon dioxide balloon would sink. The neon and hydrogen balloons would rise, with the hydrogen balloon rising at a much
faster rate.
65. Germanium, because 1210 K, is 937 °C which is less than the melting point of gold at 1064 °C
66. Improper calibration or improper use or reading of a measurement device.
67. e, d, c, f, a, b.
68. Sig figs in the answer of an addition problem depend on the measurement with the least number of significant digit decimal
places.
69. °F = °C ×
9
5
+ 32
70. a) cg b) L c) kcal d) cs e) mL f) dm3.
71. The digit to the right of the last sig fig is dropped if it is less than five.
72. 0.69 g/cm3 to 0.789 g/cm3 (from chart on p. 69)
73. Yes, an object can be moved to a location where the pull of gravity is weaker; there it will have less weight, but its mass will have
stayed the same.
74. The egg is suspended at the juncture of two liquids of different densities, and the density of the egg is less than the bottom layer
liquid, but greater than the top layer liquid.
75. a) 2 b) 1
76. It is only possible when many individual measurements are being compared to only one true value using an average as a “single”
measurement. Many accurate measurements considered separately would all come close to the true value; therefore, they would also
be precise, so in this sense, it is not possible for a series of measurements to be accurate and imprecise.
77. You would not change your estimate. The estimate has a level of significance that ends at the ten-thousand place. 15 is a number
too small that when added to the estimated value would be neglected due to the rounding rule for adding and subtracting sig figs.
78. A range of values for the density of gasoline is given because gasoline is not a pure substance, it is a mixture. Since it is a
mixture, its composition can vary and therefore will have many possible values for its properties.
Chapter 4:
33. 155.3 g
34. conversion factor
35. one
36.
1𝑔
100 𝑐𝑔
,
100 𝑐𝑔
1𝑔
,
1𝑔
,
1000 𝑚𝑔
1000 𝑚𝑔
1𝑔
,
1000 𝑚𝑔
100 𝑐𝑔
,
100 𝑐𝑔
1000 𝑚𝑔
37. They must equal each other by definition.
38. 16.3 g silver
39. The unit of the conversion factor in the denominator must be identical to the unit in the numerator from the given measurement
you’re trying to convert.
40. 720 s
41. Estimate to see if your calculator answer makes sense; round off to the correct number of significant figures.
42. 4.20 104 cm3.
43. a) 1.57 s,
157 𝑐𝑠
1
50 𝑔
1
×
b) 4.27 × 104 mL,
c) 2.61 × 104 mm,
d) 6.5 × 102 dm,
1 𝑐𝑚3
(1.19 × 10−3 )𝑔
1𝑠
100 𝑐𝑠
42.7 𝐿
×
1
261 𝑛𝑚
1
0.065 𝑘𝑚
e) 6.42 × 10‒3 kg ,
f) 8.25 × 109 ng,
×
1
642 𝑐𝑔
1
1000 𝑚𝐿
×
×
×
8.25 × 102 𝑐𝑔
1
1𝐿
1𝑚
1,000,000,000 𝑛𝑚
1000 𝑚
10 𝑑𝑚
1 𝑘𝑚
1𝑔
100 𝑐𝑔
×
×
×
1𝑔
100 𝑐𝑔
×
1000 𝑚𝑚
1𝑚
1𝑚
1 𝑘𝑔
1000 𝑔
×
1,000,000,000 𝑛𝑔
1𝑔
44. a) 7.3 μL/s,
0.44 𝑚𝐿
1 𝑚𝑖𝑛.
×
×
b) 78.6 mg/mm ,
c) 1.54
1𝐿
×
1,000,000 𝜇𝐿
×
1 𝑚𝑖𝑛.
60 𝑠
1000 𝑚𝐿
1000 𝑚𝑔
100 𝑐𝑚
2 7.86 𝑔
1 𝑐𝑚2
1𝑔
1𝐿
3 1.54 𝑘𝑔
g/cm ,
×
1𝐿
1000 𝑚𝐿
45. 1,000,000 mL,
1 𝑚3
100 𝑐𝑚
×
1
×
1𝑚
1 𝑚𝐿
×
1𝑚
×
1𝑚
×
1000 𝑚𝑚
1000 𝑚𝑚
1 𝑘𝑔
100 𝑐𝑚
×
1𝑚
1𝐿
100 𝑐𝑚
1𝑚
1000 𝑔
×
1 𝑐𝑚3
100 𝑐𝑚
×
1𝑚
×
1 𝑚𝐿
×
1𝑚
1 𝑐𝑚3
46.
47. 31.1 m/s,
mg
g
cg
kg
283
6.6 × 103
0.28
0.283
6.6
2.8 × 10‒4
28.3
660
0.028
2.83 × 10‒4
0.0066
2.8 × 10‒7
112 𝑘𝑚
1 ℎ𝑟
×
1 ℎ𝑟
60 𝑚𝑖𝑛
×
1 𝑚𝑖𝑛
60 𝑠
1000 𝑚
×
1 𝑘𝑚
48. 0.804 g/cm3, Density of H2O at 4 °C is = 1 g/cm3. So the volume of the flask must be 158 cm3, therefore, the density of ethanol is
127 g ÷ 158 cm3.
49. 3.6 min will be lost.
50. 1.1 kg/L,
1 𝑑𝑎𝑦
1
×
24 ℎ𝑟
1 𝑑𝑎𝑦
1.64 × 104 𝑔
(28.6 𝑐𝑚 ×73.0 𝑚𝑚 ×0.72 𝑚)
60 𝑚𝑖𝑛
×
×
1 ℎ𝑟
1 𝑘𝑔
1000 𝑔
×
×
0.15 𝑠
×
1 𝑚𝑖𝑛
100 𝑐𝑚
×
1𝑚
1 𝑚𝑖𝑛
60 𝑠
1000 𝑚𝑚
×
1𝑚
1𝑚
10 𝑑𝑚
1𝑚
×
10 𝑑𝑚
×
1𝑚
10 𝑑𝑚
×
1 𝑑𝑚3
1𝐿
ans. Only has 2 sig fig
because of the 0.72 m measurement which only has 2 sig fig.
52. 8.3 min.
53. 73 g,
1.5 × 108 𝑘𝑚
2.7 𝑔
1 𝑐𝑚3
×
54. 5.52 kg/dm3,
1
3.0 𝑐𝑚
1
5.52 𝑔
×
×
×
1000 𝑚
1 𝑘𝑚
3.0 𝑐𝑚
1
100 𝑐𝑚
×
×
×
1𝑠
(3.0 × 108 )𝑚
3.0 𝑐𝑚
1
100 𝑐𝑚
×
×
100 𝑐𝑚
1 𝑐𝑚3
1𝑚
1𝑚
1𝑚
40.0 𝑐𝑚
20.0 𝑐𝑚
30.0 𝑐𝑚
55. 24.0 kg of water,
×
1
1
×
1
×
1 𝑚𝑖𝑛
60 𝑠
1𝑚
×
×
1𝑚
10 𝑑𝑚
10 𝑑𝑚
1𝑔
1 𝑘𝑔
1 𝑐𝑚3
×
1000 𝑔
×
1𝑚
10 𝑑𝑚
×
1 𝑘𝑔
1000 𝑔
ans. Needs 3 sig figs, as the lengths all have 3 sig figs.
56. a) 2 b) 3
57. Ans. Vary
58. Units help to get the numbers in the right positions in conversion factors. Units help to see the math to do by cancelling out and
reaching the desired unit. Units help to plan out the correct path of conversion factors to write to get the correct answer.
62. 1235 K
962 °C + 273 = 1235 K
63. a) centigram b) kiloliter c) millisecond d) cubic decimeter (= 1 L) (1 mL = 1 cm3)
e) micrometer
65. a) 3 b) 4 c) 2 d) 4 e) 5 f) 4
66. a) 5.1 g b) 3.5 × 10 6 kg c) 7.8 × 10‒5 dm3 d) 4.5 × 10‒2 mm e) 990 K f) 65 s
Chapter 10:
20. An elastic collision transfers energy from one particle to another. There is no change in the total kinetic energy. These collisions
are said to be perfect, as no heat is generated in the collision and the particles are not deformed in their shape from the collision.
21. Pascal (Pa), Millimeter of Mercury (mmHg), and Atmosphere (atm); Pa is the SI unit
22. 16.35 atm.
23. a) 25 kPa
1656 𝑘𝑃𝑎
1
×
1 𝑎𝑡𝑚
101.3 𝑘𝑃𝑎
190 𝑚𝑚𝐻𝑔
b) 0.25 atm,
1
×
101.3 𝑘𝑃𝑎
760 𝑚𝑚𝐻𝑔
190 𝑚𝑚𝐻𝑔
&
1
×
1 𝑎𝑡𝑚
760 𝑚𝑚𝐻𝑔
ans. Only has 2 sig figs because 190 mmHg has
only 2 sig figs.
24. 2,400 mmHg
2.4 × 103 mm Hg
3.1 𝑎𝑡𝑚
1
×
760 𝑚𝑚𝐻𝑔
1 𝑎𝑡𝑚
25. Kinetic energy is directly proportional to the absolute temperature, which is measured in Kelvins.
26. The average kinetic energy of the particles is unaffected.
29. The average kinetic energy of the particles will be zero. It is therefore the coldest possible temperature matter can reach.
30. The average kinetic energy will triple.
31. Its volume is minimally affected by an increase in pressure, because its particles are still extremely close together.
32. a) The attractive forces between particles, cause liquids to have higher density than gases and for liquids to have a definite
volume.
b) The particles of liquids are very close together and cannot be squeezed together much. The particles of gases are very far apart
from each other and therefore can be compressed closer to each other by a large amount.
33. In both cases, particles with sufficient kinetic energy move from the liquid to the vapor state. In a container, a dynamic
equilibrium is set up between the liquid and its vapor.
34. Vapor pressure results from collisions of vapor particles with the container’s walls. A dynamic equilibrium exists when the rate
of evaporation of the liquid equals the rate of condensation of the vapor.
35. More particles have enough energy to escape attractions within the liquid.
36. No; vapor continuously leaves the surface of the liquid preventing dynamic equilibrium from becoming established.
37. It increases the kinetic energy, which increases the vapor pressure.
38. The boiling point is the temperature at which the vapor pressure equals the external pressure on the liquid. At the normal boiling
point, the external pressure on the liquid is 1 atm of pressure.
39. a) about 55 mmHg
b) about 93 °C
c) 760 mmHg is standard pressure (1 atm) which is why 100 °C is the normal
boiling point for water
40. about 82 °C
41. about 250 mmHg
42. Escaping particles from the liquid as gas particles, have more kinetic energy than the remaining liquid particles, as a result the
average kinetic energy left in the liquid is less than it was when the gas particles were in the liquid.
44. The solid’s particles gain sufficient kinetic energy to overcome some of the attractive forces with neighboring particles and the
particles begin to slide around each other.
46. Moisture in the food sublimated out of the food and then was deposited as ice crystals on the container lid.
47. Particles use the added heat to convert to gas particles and escape the liquid, but the average kinetic energy remains the same for
the remaining particles because heat continues to be added to them.
48. Evaporation is the conversion of a liquid to a vapor at temperature below the boiling point and only occurs to those particles at the
surface of the liquid. Vapor pressure is the force per unit area exerted by the vapor particles on the container walls. Boioling point is
the temperature at which the vapor pressure equals the external pressure.
49. about 77 °C
50. Atmospheric pressure is the result of the weight air pressing down on everything below it; the mass of air over a mountain is less
than the mass of air at lower elevations, so the air weighs less on a mountain and weighs more at lower elevations.
51. It is called a dynamic equilibrium because there are many particles moving into the vapor state and into the liquid state. So it is
dynamic because of lots of changes occurring to the particles. However, the number of particles becoming liquid is equal to the
number of particles becoming vapor, so in this sense it is in equilibrium.
52. At ‒196 °C, the kinetic energy of the air particles decreases drastically as does the pressure those gas particles exert on the walls
of the balloon, thereby reducing the balloon’s volume as the gas particles no longer hit the walls with the same force and push the
sides of the balloon outward. The kinetic energy of the air particles increases as the balloon warms back to room temperature and the
particle’s force of collision with the sides of the balloon increase and force the balloon back to its original volume.
53. It increases
54. 819 K
273 K × 3
56. a) 2 b) 1
58. They are the same kinetic energy, because they are at the same temperature.
60. The energy needed to evaporate perspiration comes from the skin, which helps lower body temperature.
61. Some chemical compounds have stronger intermolecular forces than others.
70. b. The level of mercury in the left arm of the U-tube manometer is higher, indicating less pressure pushing on the mercury in the
manometer.
71. The shape of the crystals appears to be cubic, with faces forming angles at 90°.
72. Ex. Ans. Heat the substance at atmospheric pressure until it melts. Then slowly decrease the pressure on the substance while
adjusting the temperature to keep the substance at its melting point. Then when the temperature and pressure are reached where you
have simultaneously the substance as a solid, liquid, and vapor, will be the triple point.
73. The samples each appear to be at a different temperature. The one with the longest streaks (b) implies the particles are moving
the fastest and will therefore have the most kinetic energy and be the warmest. The one with the shortest streaks (c) will be the
slowest and therefore be the coolest.
ADVANCED THINKING: They could all be at the same temperature, because temperature is a measurement of the average kinetic
energy of the particles. Kinetic energy is more than just temperature, it is also mass. The kinetic energy equation is: Kinetic Energy
= ½ mass × (velocity)2. Since the streaks only imply velocity, if the particles had different masses, they could have the same kinetic
energy. For example, a particle that is 4 times the mass of another particle, but moving at half the speed, can have the same kinetic
energy as a particle ¼ the mass moving twice as fast. Particle 1: mass = 64, velocity = 6 & Particle 2: mass = 16, velocity = 12.
Particle 1: KE = ½ (64) (62) = 32 × 36 = 1152
Particle 2: KE = ½ (16) (122) = 8 × 144 = 1152