Download Chapter 5: Gases - HCC Learning Web

Chapter 5: Gases
Section I (1 point each)
1. Which of these properties is/are characteristic(s) of gases?
A) High compressibility
B) Relatively large distances between molecules
C) Formation of homogeneous mixtures regardless of the nature of gases
D) A and B.
E) A, B, and C.
Ans: E
2. Two moles of chlorine gas at 20.0°C are heated to 350°C while the volume is kept
constant. The density of the gas
A) increases.
B) decreases.
C) remains the same.
D) Not enough information is given to correctly answer the question.
Ans: C
3. Which statement is false?
A) The average kinetic energies of molecules from samples of different "ideal" gases
is the same at the same temperature.
B) The molecules of an ideal gas are relatively far apart.
C) All molecules of an ideal gas have the same kinetic energy at constant temperature.
D) Molecules of a gas undergo many collisions with each other and the container
walls.
E) Molecules of greater mass have a lower average speed than those of less mass at
the same temperature.
Ans: C
4. The molecules of different samples of an ideal gas have the same average kinetic
energies, at the same
A) pressure. B) temperature. C) volume. D) density.
Ans: B
5. If equal masses of O2(g) and HBr(g) are in separate containers of equal volume and
temperature, which one of these statements is true?
A) The pressure in the O2 container is greater than that in the HBr container.
B) There are more HBr molecules than O2 molecules.
C) The average velocity of the O2 molecules is less than that of the HBr molecules.
D) The average kinetic energy of HBr molecules is greater than that of O2 molecules.
E) The pressures of both gases are the same.
Ans: A
Page 85
Chapter 5: Gases
6. Deviations from the ideal gas law are greater at
A) low temperatures and low pressures. C)
B) low temperatures and high pressures. D)
Ans: B
high temperatures and high pressures.
high temperatures and low pressures.
7. Samples of the following volatile liquids are opened simultaneously at one end of a room.
If you are standing at the opposite end of this room, which species would you smell first?
(Assume that your nose is equally sensitive to all these species.)
A) ethyl acetate (CH3COOC2H5)
D) naphthalene (C10H8)
B) camphor (C10H16O)
E) pentanethiol (C5H11SH)
C) diethyl ether (C2H5OC2H5)
Ans: C
8. What is standard temperature and standard pressure?
Ans: 0°C and 1 atm pressure
9. Give five examples of elements and five examples of compounds that occur as gases at
room temperature and pressure?
Ans: (Answers will vary.) Oxygen, nitrogen, helium, hydrogen, argon, chlorine
CO2, CO, NO2, SF6, SO2, H2S
10. At constant pressure, the density of a gas depends on temperature. Does the density
increase or decrease as the temperature increases?
Ans: decrease
Page 86
Chapter 5: Gases
Section II (4 points each)
1. A sample of a gas occupies 1.40  103 mL at 25°C and 760 mmHg. What volume will it
occupy at the same temperature and 380 mmHg? (Const. Temp, P1V1 = P2V2)
2800 mL / 2.8 L
2. A sample of nitrogen gas has a volume of 32.4 L at 20°C. The gas is heated to 220ºC at
constant pressure. What is the final volume of nitrogen? (Const. Pressure, V1/T1 = V2/T2)
54.5 L
3. If 30.0 L of oxygen are cooled from 200ºC to 1°C at constant pressure, what is the new
volume of oxygen? (Const. Pressure, V1/T1 = V2/T2)
17.4 L
4. The gas pressure in an aerosol can is 1.8 atm at 25°C. If the gas is an ideal gas, what
pressure would develop in the can if it were heated to 475°C? (P1/T1 = P2/T2)
4.52 atm
5. A small bubble rises from the bottom of a lake, where the temperature and pressure are
4°C and 3.0 atm, to the water's surface, where the temperature is 25°C and the pressure is
0.95 atm. Calculate the final volume of the bubble if its initial volume was 2.1 mL.
(Combined gas law, P1V1/T1 = P2V2/T2)
7.13 mL
6. The temperature of an ideal gas in a 5.00 L container originally at 1 atm pressure and
25°C is lowered to 220 K. Calculate the new pressure of the gas. (P1/T1 = P2/T2)
0.738 atm
7. Calculate the number of moles of gas contained in a 10.0 L tank at 22°C and 105 atm. (R
= 0.08206 Latm/Kmol) (PV = nRT)
43.4 (43.37) mol
8. Calculate the density, in g/L, of CO2 gas at 27°C and 0.50 atm pressure. (d = PM/RT)
M=molar mass
0.89 g/L
Page 87
Chapter 5: Gases
9. What is the molar mass of Freon-11 gas if its density is 6.13 g/L at STP? (d = PM/RT)
137.3 g/mol
10. A mixture of three gases has a total pressure of 1,380 mmHg at 298 K. The mixture is
analyzed and is found to contain 1.27 mol CO2, 3.04 mol CO, and 1.50 mol Ar. What is
the partial pressure of Ar? (Pi = XiPT)
356 mmHg (0.46 atm)
11. What volume of CO2 gas at 645 torr and 800 K could be produced by the reaction of 45 g
of CaCO3 according to the equation? (19.8 g, 0.45 mol, 1 mol @STP occupies 22.4 L, so
0.45 mol occupies 10.08 L, then use P1V1/T1 = P2V2/T2, PV=nRT)
CaCO3(s)  CaO(s) + CO2(g)
34.8 L
12. How many grams of N2O, nitrous oxide, are contained in 500. mL of the gas at STP? (1
mol @ STP occupies 22.4 L, 0.5 L will be 0.02232 mol, x mol wt. of N2O (44)) or
(PV=nRT, n=0.02232 mol )
Ans: 0.982 g
13. Calculate the density of N2O gas, in grams per liter, at 110°C and 12 atm. (d = PM/RT)
Ans: 16.8 g/L
14. Calculate the molar mass of a gaseous substance if 0.125 g of the gas occupies 93.3 mL
at STP. (1 mol @ STP = 22.4 L, 4.165 x 10-3 mol = 0.125 g, 1 mol is how many g) OR
m/v=d and then d = PM/RT)
Ans: 30.01 g/mol
15. What volume of H2 is formed at STP when 6.0 g of Al is treated with excess NaOH?
2NaOH + 2Al + 6H2O  2NaAl(OH)4 + 3H2(g)
Ans: 7.46 L
Page 88
Chapter 5: Gases
Chapter 6: Thermochemistry
1. Radiant energy is
A) the energy stored within the structural units of chemical substances.
B) the energy associated with the random motion of atoms and molecules.
C) solar energy, i.e. energy that comes from the sun.
D) energy available by virtue of an object's position.
Ans: C Category: Easy Section: 6.1
2. Thermal energy is
A) the energy stored within the structural units of chemical substances.
B) the energy associated with the random motion of atoms and molecules.
C) solar energy, i.e. energy that comes from the sun.
D) energy available by virtue of an object's position.
Ans: B Category: Easy Section: 6.1
3. Chemical energy is
A) the energy stored within the structural units of chemical substances.
B) the energy associated with the random motion of atoms and molecules.
C) solar energy, i.e. energy that comes from the sun.
D) energy available by virtue of an object's position.
Ans: A Category: Easy Section: 6.1
4. Potential energy is
A) the energy stored within the structural units of chemical substances.
B) the energy associated with the random motion of atoms and molecules.
C) solar energy, i.e. energy that comes from the sun.
D) energy available by virtue of an object's position.
Ans: D Category: Easy Section: 6.1
5. Heat is
A) a measure of temperature.
B) a measure of the change in temperature.
C) a measure of thermal energy.
D) a measure of thermal energy transferred between two bodies at different
temperature.
Ans: D Category: Medium Section: 6.2
6. An endothermic reaction causes the surroundings to
A) warm up.
D) decrease in temperature.
B) become acidic.
E) release CO2.
C) condense.
Ans: D Category: Easy Section: 6.2
Page 89
Chapter 5: Gases
7. An exothermic reaction causes the surroundings to
A) warm up.
D) decrease its temperature.
B) become acidic.
E) release CO2.
C) expand.
Ans: A Category: Easy Section: 6.2
8. Copper metal has a specific heat of 0.385 J/g·°C. Calculate the amount of heat required to
raise the temperature of 22.8 g of Cu from 20.0°C to 875°C.
A) 1.97  10–5 J B) 1.0  10–2 J C) 329 J D) 7.51 kJ E) 10.5 kJ
Ans: D Category: Medium Section: 6.5
9. Calculate the amount of heat necessary to raise the temperature of 12.0 g of water from
15.4°C to 93.0°C. The specific heat of water = 4.18 J/g·°C.
A) 0.027 J B) 324 J C) 389 J D) 931 J E) 3,890 J
Ans: E Category: Medium Section: 6.5
10. How much heat is required to raise the temperature of 2,500 g of water from 27°C to
72°C? The specific heat of water is 4.184 J/g·°C.
A) 0.19 kJ B) 10. kJ C) 280 kJ D) 470 kJ E) 750 kJ
Ans: D Category: Medium Section: 6.5
11. A beaker contains 115 g of ethanol at 18.2°C. If the ethanol absorbs 1125 J of heat
without losing heat to the surroundings, what will be the final temperature of the ethanol?
The specific heat of ethanol is 2.46 J/g°C.
A) 4.08°C B) 14.1°C C) 18.4°C D) 22.2°C E) 36.4°C
Ans: D Category: Medium Section: 6.5
12. How many degrees of temperature rise will occur when a 25.0 g block of aluminum
absorbs 10.0 kJ of heat? The specific heat of Al is 0.900 J/g·°C.
A) 0.44°C B) 22.5°C C) 225°C D) 360°C E) 444°C
Ans: E Category: Medium Section: 6.5
13. If 325 g of water at 4.2°C absorbs 12.28 kJ, what is the final temperature of the water?
The specific heat of water is 4.184 J/g·°C.
A) 4.21°C B) 4.8°C C) 9.0°C D) 13.2°C E) 2,938°C
Ans: D Category: Medium Section: 6.5
14. A glass containing 200. g of H2O at 20°C was placed in a refrigerator. The water loses
11.7 kJ as it cools to a constant temperature. What is its new temperature? The specific
heat of water is 4.184 J/g·°C.
A) 0.013°C B) 4°C C) 6°C D) 14°C E) 34°C
Ans: C Category: Medium Section: 6.5
Page 90
Chapter 5: Gases
15. A piece of copper with a mass of 218 g has a heat capacity of 83.9 J/°C. What is the
specific heat of copper?
A) 0.385 J/g·°C
D) 1.32 J/g·°C
4
B) 1.83  10 J/g·°C
E) 24.5 J/g·°C
C) 2.60 J/g·°C
Ans: A Category: Easy Section: 6.5
16. The specific heat of gold is 0.129 J/g·°C. What is the molar heat capacity of gold?
A) 0.039 J/mol·°C
D) 39.0 kJ/mol·°C
B) 0.129 J/mol·°C
E) 197 J/mol·°C
C) 25.4 J/mol·°C
Ans: C Category: Easy Section: 6.5
17. Which of the following processes is endothermic?
A) O2(g) + 2H2(g)  2H2O(g)
B) H2O(g)  H2O(l)
C) 3O2(g) + 2CH3OH(g)  2CO2(g) + 2H2O(g)
D) H2O(s)  H2O(l)
Ans: D Category: Medium Section: 6.4
18. A 100. mL sample of 0.200 M aqueous hydrochloric acid is added to 100. mL of 0.200 M
aqueous ammonia in a calorimeter whose heat capacity (excluding any water) is 480. J/K.
The following reaction occurs when the two solutions are mixed.
HCl(aq) + NH3(aq)  NH4Cl(aq)
The temperature increase is 2.34°C. Calculate H per mole of HCl and NH3 reacted.
A) 154 kJ/mol
D) –1.96 kJ/mol
B) 1.96 kJ/mol
E) –154 kJ/mol
C) 485 kJ/mol
Ans: E Category: Difficult Section: 6.5
Ans: q = m x S x t, [(200 x 4.184 x 2.34 = 1958.112) + (480 x 2.34 = 1123.2) / 0.02 mol]
19. Octane (C8H18) undergoes combustion according to the following thermochemical
equation:
2C8H18(l) + 25O2(g)  16CO2(g) + 18H2O(l)
H°rxn = –11,020 kJ/mol.
Given that H°f[CO2(g)] = –393.5 kJ/mol and H°f[H2O(l)] = –285.8 kJ/mol, calculate
the standard enthalpy of formation of octane.
A) –210 kJ/mol
D) –420 kJ/mol
B) –11,230 kJ/mol
E) 420 kJ/mol
C) 22,040 kJ/mol
Ans: A Category: Medium Section: 6.6
Page 91
Chapter 5: Gases
20. Glycine, C2H5O2N, is important for biological energy. The combustion reaction of
glycine is given by the equation
4C2H5O2N(s) + 9O2(g)  8CO2(g) + 10H2O(l) + 2N2(g)
H°rxn = –3857 kJ/mol
Given that H°f[CO2(g)] = –393.5 kJ/mol and H°f[H2O(l)] = –285.8 kJ/mol, calculate
the enthalpy of formation of glycine.
A) –537.2 kJ/mol
D) –3,178 kJ/mol
B) –268.2 kJ/mol
E) –964 kJ/mol
C) 2,149 kJ/mol
Ans: A Category: Medium Section: 6.6
21. Calculate the standard enthalpy of formation of liquid methanol, CH3OH(l), using the
following information:
C(graph) + O2  CO2(g)
H° = –393.5 kJ/mol
H2(g) + (1/2)O2  H2O(l)
H° = –285.8 kJ/mol
CH3OH(l) + (3/2)O2(g)  CO2(g) + 2H2O(l)
H° = –726.4 kJ/mol
A)
B)
C)
Ans:
–1,691.5 kJ/mol
–238.7 kJ/mol
1691.5 kJ/mol
B Category: Difficult
D)
E)
47.1 kJ/mol
–47.1 kJ/mol
Section: 6.6
22. Calculate the standard enthalpy change for the reaction
2C8H18(l) + 17O2(g)  16CO(g) + 18H2O(l).
Given:
2C8H18(l) + 25O2(g) 16CO2(g) + 18H2O(l) H° = –11,020 kJ/mol
2CO(g) + O2(g)  2CO2(g)
H° = –566.0 kJ/mol
A) 10,450 kJ/mol
D) –6,492 kJ/mol
B) 6,492 kJ/mol
E) –10.450 kJ/mol
C) 15,550 kJ/mol
Ans: D Category: Medium Section: 6.6
23. During volcanic eruptions, hydrogen sulfide gas is given off and oxidized by air
according to the following chemical equation:
2H2S(g) + 3O2(g)  2SO2(g) + 2H2O(g)
Calculate the standard enthalpy change for the above reaction given:
3S(s) + 2H2O(g)  2H2S(g) + SO2(g)
H° = 146.9 kJ/mol
S(s) + O2(g)  SO2(g)
H° = –296.4 kJ/mol
A)
B)
C)
Ans:
–1036.1 kJ/mol
–742.3 kJ/mol
–149.5 kJ/mol
A Category: Medium
D)
E)
Section: 6.6
Page 92
443.3 kJ/mol
742.3 kJ/mol
Chapter 5: Gases
24. Calculate the standard enthalpy change for the reaction
2C8H18(l) + 21O2(g)  8CO(g) + 8CO2(g) + 18H2O(l).
Given:
2C8H18(l) + 25O2(g)  16CO2(g) + 18H2O(l)
H° = –11,020 kJ/mol
2CO(g) + O2(g)  2CO2(g)
H° = –566.0 kJ/mol
A) 1.0454  104 kJ/mol
D) –6,492 kJ/mol
B) –8,756 kJ/mol
E) –1.0454  104 kJ/mol
C) 1.1586  104 kJ/mol
Ans: B Category: Medium Section: 6.6
25. Given the thermochemical equation 2SO2 + O2  2SO3, H°rxn = –198 kJ/mol,
what is the standard enthalpy change for the decomposition of one mole of SO3?
A) 198 kJ/mol
D) 396 kJ/mol
B) –99 kJ/mol
E) –198 kJ/mol
C) 99 kJ/mol
Ans: C Category: Medium Section: 6.6
26. Given H2(g) + (1/2)O2(g)  H2O(l), H° = –286 kJ/mol, determine the standard enthalpy
change for the reaction 2H2O(l)  2H2(g) + O2(g).
A) H° = –286 kJ/mol
D) H° = +572 kJ/mol
B) H° = +286 kJ/mol
E) H° = –143 kJ/mol
C) H° = –572 kJ/mol
Ans: D Category: Easy Section: 6.6
27. An average home in Colorado requires 20. GJ of heat per month. How many grams of
natural gas (methane) must be burned to supply this energy?
CH4(g) + 2O2(g)  CO2(g) + 2H2O(l) H°rxn= –890.4 kJ/mol
A) 1.4  103 g
D) 2.2  104 g
B) 3.6  105 g
E) 1.4  104 g
C) 7.1  10–4 g
Ans: B Category: Medium Section: 6.4
28. According to the first law of thermodynamics:
A) Energy is neither lost nor gained in any energy transformations.
B) Perpetual motion is possible.
C) Energy is conserved in quality but not in quantity.
D) Energy is being created as time passes. We have more energy in the universe now
than when time began.
Ans: A Category: Easy Section: 6.3
29. A gas is compressed in a cylinder from a volume of 20.0 L to 2.0 L by a constant
pressure of 10.0 atm. Calculate the amount of work done on the system.
A) 1.01  104 J B) –180 J C) 1.81  104 J D) –1.81  104 J E) 180 J
Ans: C
Category: Medium Section: 6.3
Page 93
Chapter 5: Gases
30. Calculate the amount of work done against an atmospheric pressure of 1.00 atm when
500.0 g of zinc dissolves in excess acid at 30.0°C. (Use W = -PV, Find V using
PV=nRT, V is same as V=Vol of H2 produced)
Zn(s) + 2H+(aq)  Zn2+(aq) + H2(g)
A) w = +22.4 kJ
D) w = –2.52 kJ
B) w = +24.9 kJ
E) w = –19.3 kJ
C) w = 0
Ans: E Category: Medium Section: 6.3
31. Define specific heat.
Ans: The amount of heat required to raise the temperature of one gram of a substance by
one degree Celsius.
Category: Easy Section: 6.5
32. How many grams of ethylene (C2H4) would have to be burned to produce 450 kJ of heat?
C2H4(g) + 3O2(g)  2CO2(g) + H2O(l)
H°rxn = –1411 kJ/mol
Ans: 8.95 g
Category: Medium Section: 6.4
33. Calculate the enthalpy of reaction for H2(g) + C2H4(g)  C2H6(g).
[H°f(C2H4(g)) = 52.3 kJ/mol; H°f(C2H6(g)) = –84.7 kJ/mol]
Ans: –137 kJ/mol
Category: Medium Section: 6.6
34. The enthalpy of combustion of acetylene C2H2 is described by
C2H2(g) + (5/2)O2(g)  2CO2(g) + H2O(l) H°rxn= –1299 kJ/mol
Calculate the enthalpy of formation of acetylene, given the following enthalpies of
formation
H°f[CO2(g)] = –393.5 kJ/mol
H°f[H2O(l)] = –285.8 kJ/mol
Ans: 226 kJ/mol
Category: Medium Section: 6.6
35. Given the following H° values,
H2(g) + 1 2 O2(g)  H2O(l) H°f = –285.8 kJ/mol
H2O2(l)  H2(g) + O2(g) H°rxn = 187.6 kJ/mol
calculate H°rxn for the reaction H2O2(l)  H2O(l) +
Ans: –98.2 kJ/mol
Category: Medium Section: 6.6
1
2
O2(g),
36. A 26.2 g piece of copper metal is heated from 21.5°C to 201.6°C. Calculate the amount
of heat absorbed by the metal. The specific heat of Cu is 0.385 J/g·°C.
Ans: 1,816.67 J
Category: Medium Section: 6.5
Page 94
Chapter 5: Gases
37. The value of H°rxn for the following reaction is –6535 kJ/mol.
2C6H6(l) + 15O2(g)  12CO2(g) + 6H2O(g)
How many kilojoules of heat will be evolved during the combustion of 16.0 g of C6H6(l)?
Ans: 669 kJ
Category: Medium Section: 6.4
38. What would be the standard enthalpy change for the reaction of one mole of H2(g) with
one mole of Cl2(g) to produce two moles of HCl(g) at standard state conditions?
[H°f (HCl(g))= –92.3 kJ/mol]
Ans: –185 kJ
Category: Medium Section: 6.6
39. What is the standard enthalpy of formation of H2(g) at 25°C?
Ans: 0 kJ/mol
Category: Easy Section: 6.6
40. Find H°rxn for the reaction
CH4(g) + 2O2(g)  CO2(g) + 2H2O(l).
[H°f (CH4(g)) = –74.8 kJ/mol; H°f (CO2(g)) = –393.5 kJ/mol; H°f (H2O(l)) = –285.5
kJ/mol]
Ans: -889.7 kJ/mol
Category: Medium Section: 6.6
41. Find H°rxn for the reaction
2Ag2S(s) + 2H2O(l)  4Ag(s) + 2H2S(g) + O2(g).
[H°f (Ag2S(s)) = –32.6 kJ/mol; H°f (H2S(g)) = –20.5 kJ/mol; H°f (H2O(l)) = –285.5
kJ/mol]
Ans: 595.2 kJ/mol
Category: Medium Section: 6.6
42. Find H°rxn for the reaction
2Na(s) + 2H2O(l)  2NaOH(aq) + 2H2(g).
[H°f (NaOH(aq)) = –426.8 kJ/mol; H°f (H2O(l)) = –285.5 kJ/mol]
Ans: –282.6 kJ/mol
Category: Medium Section: 6.6
43. The specific heat of silver is 0.235 J/g·°C. How many joules of heat are required to heat
a 75 g silver spoon from 20°C to 35°C?
Ans: 260 (264.38) J
Category: Easy Section: 6.5
Page 95
Chapter 5: Gases
44. At body temperature 2,404 joules of energy are required to evaporate 1.00 g of water.
After vigorous exercise, a person feels chilly because the body is giving up heat to
evaporate the perspiration. A typical person perspires 25 mL of water after 20. minutes of
exercise. How much body heat is this person using to evaporate this water?
Ans: 6.0  104 J (60.1 kJ)
Category: Easy Section: 6.4
45. The heat capacity of 20.0 g of water is 83.7 J/°C.
Ans: True Category: Medium Section: 6.5
46. The work done on the surroundings by the expansion of a gas is w = –PV.
Ans: True Category: Easy Section: 6.3
47. The heat absorbed by a system at constant pressure is equal to E + PV.
Ans: True Category: Easy Section: 6.4
48. In an endothermic process, heat is absorbed by the system.
Ans: True Category: Easy Section: 6.2
49. A home aquarium is an example of an open system.
Ans: True Category: Easy Section: 6.2
50. The heat of hydration (Hhydr) of ions is always endothermic.
Ans: False Category: Medium Section: 6.7
Page 96
Chapter 5: Gases
Chapter 7: (2 points each)
1. In the following diagram of a wave
A)
B)
C)
Ans:
(a) is amplitude and (b) is wavelength D)
(a) is frequency and (b) is amplitude E)
(a) is wavelength and (b) is frequency
E
(a) is amplitude and (b) is frequency
(a) is wavelength and (b) is amplitude
2. What is the wavelength of radiation that has a frequency of 5.39  1014 s–1? (c = 2.9979 
108 m/s) ( = c / )
A) 1.80  10–3 nm B) 556 nm C) 618 nm D) 6180 nm E) 1.61  1023 nm
Ans: B
3. Calculate the frequency of visible light having a wavelength of 686 nm. ( = c / )
A) 4.37  1014 /s
D) 2.29  10–15 /s
5
B) 4.37  10 /s
E) 2.29  10–6 /s
C) 6.17  1014 /s
Ans: A
Page 97
Chapter 5: Gases
4. Which one of the following sets of quantum numbers is not possible?
Ans: B
5. Which one of the following sets of quantum numbers is not possible?
Ans: B
6. What is the maximum number of electrons in an atom that can have the following set of
quantum numbers?
n = 4 l = 3 ml = –2 ms = +1/2
A) 0 B) 1 C) 2 D) 6 E) 10
Ans: B
7. A possible set of quantum numbers for the last electron added to complete an atom of
gallium (Ga) in its ground state is
Ans: C
Page 98
Chapter 5: Gases
8. A possible set of quantum numbers for the last electron added to complete an atom of
germanium (Ge) in its ground state is
Ans: C
9. Electrons in an orbital with l = 3 are in a/an
A) d orbital. B) f orbital. C) g orbital. D) p orbital.
Ans: B
E) s orbital.
10. The number of orbitals in a d subshell is
A) 1 B) 2 C) 3 D) 5 E) 7
Ans: D
11. "No two electrons in an atom can have the same four quantum numbers" is a statement of
A) the Pauli exclusion principle.
D) de Broglie's relation.
B) Bohr's equation.
E) Dalton's atomic theory.
C) Hund's rule.
Ans: A
12. The orbital diagram for a ground-state nitrogen atom is
Ans:
A
Page 99
Chapter 5: Gases
13. The orbital diagram for a ground-state oxygen atom is
Ans: D
14. The orbital diagram for a ground state carbon atom is
Ans: D
Page 100
Chapter 5: Gases
15. Which ground-state atom has an electron configuration described by the following orbital
diagram?
A) phosphorus
Ans: C
B) germanium
C) selenium
D) tellurium
E) none of these
16. Which ground-state atom has an electron configuration described by the following orbital
diagram?
A) antimony B) germanium
Ans: E
C) indium
D) lead
E) tin
17. Which ground-state atom has an electron configuration described by the following orbital
diagram?
A) phosphorus
Ans: A
B) nitrogen
C) arsenic D) vanadium
Page 101
E) none of these
Chapter 5: Gases
18. How many unpaired electrons does a ground-state atom of sulfur have?
A) 0 B) 1 C) 2 D) 3 E) 4
Ans: C
19. A ground-state atom of arsenic has
A) no unpaired electrons.
B) one unpaired electron.
C) two unpaired electrons.
Ans: D
D)
E)
three unpaired electrons.
four unpaired electrons.
20. Which element has the following ground-state electron configuration?
1s22s22p63s2
A) Na B) Mg C) Al D) Si E) Ne
Ans: B
21. Which element has the following ground-state electron configuration?
[Ar]4s23d104p5
A) aresnic B) bromine C) iodine D) selenium E) tellerium
Ans: B
22. Which element has the following ground-state electron configuration?
[Kr]5s14d5
A) Mn B) Mo C) Nb D) Re E) Tc
Ans: B
23. Which element has the following ground-state electron configuration?
[Kr]5s24d105p2
A) Sn B) Sb C) Pb D) Ge E) Te
Ans: A
24. The electron configuration of a ground-state Co atom is
A) [Ar]4s23d7
D) [Ar]4s13d5
2 2 6 2 9
B) 1s 2s 2p 3s 3d
E) [Ar]4s24d7
C) [Ne]3s23d7
Ans: A
Page 102
Chapter 5: Gases
25. The electron configuration of a ground-state vanadium atom is
A) [Ar]4s24d3 B) [Ar]4s24p3 C) [Ar]4s23d3 D) [Ar]3d5
Ans: C
26. The electron configuration of a ground-state copper atom is
A) [Ar]4s24d4 B) [Ar]4s24p63d3 C) [Ar]4s23d9 D) [Ar]3d9
Ans: E
E) [Ar]4s13d10
27. The ground-state electron configuration for an atom of indium is
A) [Kr]5s24p64d5
D) [Kr]5s25p64d5
B) [Ar]4s23d104p1
E) [Kr]5s24d105p1
2 6 5
C) [Ar]4s 4p 3d
Ans: E
28. Which of the following is the ground-state electron configuration of a calcium atom?
A) [Ne]3s2 B) [Ne]3s23p6 C) [Ar]4s13d1 D) [Ar]4s2 E) [Ar]3d2
Ans: D
29. How many electrons are there in the 2nd principal energy level (n = 2) of a phosphorus
atom?
A) 3 B) 5 C) 6 D) 8 E) 10
Ans: D
30. How many electrons are there in the 3rd principal energy level (n = 3) of a phosphorus
atom?
A) 3 B) 5. C) 6 D) 8 E) 10
Ans: B
31. A ground-state atom of manganese has ___ unpaired electrons and is _____.
A) 0, diamagnetic
D) 5, paramagnetic
B) 2, diamagnetic
E) 7, paramagnetic
C) 3, paramagnetic
Ans: D
32. A ground-state atom of vanadium has ___ unpaired electrons and is _____.
A) 0, diamagnetic
D) 5, paramagnetic
B) 2, diamagnetic
E) 4, diamagnetic
C) 3, paramagnetic
Ans: C
Page 103
Chapter 5: Gases
33. A ground-state atom of iron has ___ unpaired electrons and is _____.
A) 0, diamagnetic
D) 5, paramagnetic
B) 6, diamagnetic
E) 4, paramagnetic
C) 3, paramagnetic
Ans: E
34. A ground-state chromium atom has how many unpaired electrons?
A) 1 B) 2 C) 4 D) 5 E) 6
Ans: E
35. An AM radio station broadcasts at a frequency of 1270 kHz. Calculate the wavelength of
the broadcast signal in meters. (c = 2.9979  108 m/s  = C/)
Ans: 236 m
36. Write the ground state electron configuration for the selenium atom.
Ans: [Ar] 4s23d104p4
37. Write the ground state electron configuration for the phosphorus atom.
Ans: [Ne] 3s23p3
38. Write the ground state electron configuration for Ni.
Ans: [Ar] 4s23d8
39. Write the ground state electron configuration for Cr.
Ans: [Ar] 4s13d5
40. Calculate the energy of a photon of light with a wavelength of 360 nm.
Ans: 5.53  10 –19 J
41. What is the total number of electrons possible in the 2p orbitals?
Ans: 6
42. What is the total number of electrons possible in the 6s orbital?
Ans: 2
43. What is the ground-state electron configuration for chlorine?
Ans: 1s22s22p63s23p5 or [Ne]3s23p5
44. If one electron is added to the outer shell of chlorine, it would have the same electron
configuration as what element?
Ans: argon
45. The colors of the visible spectrum are blue, green, orange, red, violet, and yellow. Of
these colors, _______ has the most energy.
Ans: violet
Page 104
Chapter 5: Gases
46. The colors of the visible spectrum are blue, green, orange, red, violet, and yellow. Of
these colors, ______ has the least energy.
Ans: red
47. The colors of the visible spectrum are blue, green, orange, red, violet, and yellow. Of
these colors, _______ has the longest wavelength.
Ans: red
48. The colors of the visible spectrum are blue, green, orange, red, violet, and yellow. Of
these colors, ______ has the shortest wavelength.
Ans: violet
49. A neon atom in its ground state will be diamagnetic (True or False).
Ans: True
50. For all atoms of the same element, the 2s orbital is larger than the 1s orbital (True or
False).
Ans: True
Page 105
Chapter 5: Gases
Chapter 8: (2 points each)
1. The elements in Group 7A are known by what name?
A) transition metals
D) alkaline earth metals
B) halogens
E) noble gases
C) alkali metals
Ans: B
2. The elements in Group 2A are known by what name?
A) transition metals
D) alkaline earth metals
B) halogens
E) noble gases
C) alkali metals
Ans: D
3. The alkali metal elements are found in _______ of the periodic table.
A) Group 1A B) Group 2A C) Group 3A D) Period 7 E) Period 1
Ans: A
4. Which one of the following elements is a transition element?
A) Sr B) Pb C) As D) Fe E) H
Ans: D
5. Which one of the following elements is a transition element?
A) antimony B) barium C) chromium D) potassium E) selenium
Ans: C
6. The general electron configuration for atoms of all elements in Group 5A is
A) ns2np6 B) ns2np5 C) ns2np4 D) ns2np3 E) ns2np1
Ans: D
7. Which of the following is the general electron configuration for the outermost electrons
of elements in the alkaline earth group?
A) ns1 B) ns2 C) ns2np4 D) ns2np5 E) ns2np6(n -1)d6
Ans: B
8. The general electron configuration for atoms of the halogen group is
A) ns2np6 B) ns2np5 C) ns2np6(n -1)d7 D) ns1 E) ns2np7
Ans: B
9. The general electron configuration for noble gas atoms is
A) ns2np6 B) ns2np5 C) ns2np4 D) ns2np3 E) ns2
Ans: A
Page 106
Chapter 5: Gases
10. An element with the general electron configuration for its outermost electrons of ns2np1
would be in which element group?
A) 2A B) 3A C) 4A D) 5A E) 8A
Ans: B
11. How many valence electrons does an oxygen atom have?
A) 2 B) 4 C) 6 D) 7 E) 8
Ans: C
12. How many valence electrons does a tin (Sn) atom have?
A) 2 B) 4 C) 14 D) 36 E) 50
Ans: B
13. How many electrons are in the 4p orbitals of vanadium?
A) 0 B) 2 C) 4 D) 5 E) 6
Ans: A
14. What is the charge on the monatomic ion that calcium forms in its compounds?
A) +2 B) +1 C) –1 D) –2 E) –3
Ans: A
15. What is the charge on the monatomic ion of nitrogen, the nitride ion?
A) +2 B) +1 C) –1 D) –2 E) –3
Ans: E
16. Which two electron configurations represent elements that would have similar chemical
properties?
(1) 1s22s22p4
(2) 1s22s22p5
(3) [Ar]4s23d5
(4) [Ar]4s23d104p5
A) (1) and (2) B) (1) and (3) C) (2) and (3) D) (2) and (4) E) (3) and (4)
Ans: D
17. Which one of the following pairs are isoelectronic?
A) Mn2+ and Ar
D) Cl– and S
2+
2+
B) Zn and Cu
E) K+ and Cl–
C) Na+ and K+
Ans: E
18. Which ion is isoelectronic with Ar?
A) Fe2+ B) F– C) Br– D) Ga3+
Ans: E
E) Ca2+
19. Which of the following is the electron configuration of the iron(III) ion?
A) [Ar]3d5 B) [Ar]4s13d5 C) [Ar]4s23d3 D) [Ar]3d6 E) [Ar]4s23d9
Ans: A
Page 107
Chapter 5: Gases
20. The electron configuration of a copper(I) ion is
A) [Ar]4s23d8 B) [Ar]4s13d9 C) [Ar]4s03d10 D) [Ar]4s23d64p2
Ans: C
E) [Kr]
21. The sulfide ion, S2–, is isoelectronic with which one of the following?
A) O2– B) F– C) Na+ D) Al3+ E) K+
Ans: E
22. The cobalt(III) ion, Co3+, has how many 3d electrons?
A) 0 B) 7 C) 6 D) 5 E) 4
Ans: C
23. How many 3d electrons does the manganese(II) ion, Mn2+, have?
A) 3 B) 4 C) 5 D) 6 E) 7
Ans: C
24. How many 3d electrons does an Fe3+ ion have?
A) 9 B) 6 C) 5 D) 4 E) 3
Ans: C
25. Which of the following ground-state ions has the largest number of unpaired electrons?
A) Cr2+ B) Mn2+ C) Ni2+ D) Cu+ E) Co2+
Ans: B
26. Which of the following ground-state ions has unpaired electrons?
A) P3– B) V5+ C) Mg2+ D) Sc2+ E) S2+
Ans: D and E
27. Which of the atoms listed below has the smallest radius?
A) Al B) P C) As D) Te E) Na
Ans: B
28. Which of the elements listed below has the greatest atomic radius?
A) B B) Al C) S D) P E) Si
Ans: B
29. Which one of the following ions has the largest radius?
A) Cl– B) K+ C) S2– D) Na+ E) O2–
Ans: C
Page 108
Chapter 5: Gases
30. Arrange the following ions in order of increasing ionic radius: K+, P3– , S2–, Cl–.
increasing radius 
A) K+ < Cl– < S2– < P3–
D) Cl– < S2– < P3– < K+
+
3–
2–
–
B) K < P < S < Cl
E) Cl– < S2– < K+ < P3–
C) P3– < S2– < Cl– < K+
Ans: A
31. Arrange the following ions in order of decreasing ionic radius: Al3+, Mg2+, Na+, O2–.
decreasing radius 
A) Al3+ > Mg2+ > O2– > Na+
D) O2– > Al3+ > Mg2+ > Na+
3+
2+
+
2–
B) Al > Mg > Na > O
E) O2– > Na+ > Mg2+ > Al3+
C) Na+ > Mg2+ > Al3+ > O2–
Ans: E
32. Which of the elements listed below has the highest first ionization energy?
A) He B) Ne C) Ar D) Kr E) Xe
Ans: A
33. Which of the elements listed below has the highest first ionization energy?
A) C B) Ge C) P D) O E) Se
Ans: D
34. Which of the following elements has the smallest first ionization energy?
A) Cl B) Na C) Be D) K E) As
Ans: D
35. Which of the following elements has the smallest ionization energy?
A) Li B) Na C) Be D) K E) Rb
Ans: E
36. Which of the following elements has the greatest electron affinity (largest positive
value)?
A) Mg B) Al C) Si D) P E) S
Ans: E
37. Which of the following is an amphoteric oxide?
A) Na2O B) MgO C) Al2O3 D) SO2 E) Cl2O7
Ans: C
38. Which of the following is an acidic oxide?
A) P4O10 B) MgO C) Fe2O3 D) K2O
Ans: A
Page 109
E) Cr2O3
Chapter 5: Gases
39. Which of the following is a basic oxide?
A) NO2 B) H2O C) Na2O D) SnO
Ans: C
E) SO2
40. Consider the following reaction: 3Li + Z  Li3Z. What is the formula for the compound
if we substitute sodium for lithium?
A) NaZ B) Na2Z C) NaZ2 D) Na3Z E) NaZ3
Ans: D
41. Consider the following reaction: 3Li + Z  Li3Z. What is the formula for the compound
if we substitute magnesium for lithium?
A) MgZ B) Mg2Z C) MgZ2 D) Mg3Z E) Mg3Z2
Ans: E
42. Write the ground-state electron configuration for S2–.
Ans: [Ar]
43. Write the ground-state electron configuration for Cr3+.
Ans: [Ar]3d3
44. Write the ground-state electron configuration for Ni2+.
Ans: [Ar]3d8
45. Write the ground-state electron configuration for Br–.
Ans: [Kr]
46. Write the ground-state electron configuration for K+.
Ans: [Ar]
47. Why is the Mg2+ ion smaller than F–, even though they are isoelectronic?
Ans: Mg2+ has a higher nuclear charge than F–
48. The radii of ions are always smaller than the radii of the corresponding atoms of the same
element. (True or False)
Ans: False
49. The electron configuration of the outermost electrons of atoms of the halogen group is
ns2np7. (True or False)
Ans: False
50. Amphoteric oxides exhibit both acidic and basic properties. (True or False)
Ans: True
Page 110