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The properties of gases

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Atkins & de Paula: Elements of Physical Chemistry, Seventh Edition ANSWERS TO END OF CHAPTER EXERCISES 1 Focus 1 The properties of gases Answers to exercises Topic 1A The perfect gas 1A.1 (a) 810 Torr (b) 0.962 atm (c) 0.222 atm (d) 1.03 Γ— 10 5 Pa 1A.2 92 kPa 1A.3 2.25 kPa 1A.4 4.33 mmol 1A.5 660 bar 1A.6 10.0 atm 1A.7 418 kPa 1A.8 173 kPa 1A.9 βˆ’243.6 ℃ 1A.10 394 K 1A.11 (a) 3.6 m 3 (b) 178 m 3 1A.12 3.4 Γ— 10 5 m 3 1A.13 benzene 0.355, toluene 0.645 1A.14 (a) 1.32 Γ— 10 βˆ’3 m 3 (b) 61.2 Γ— 10 3 Pa Topic 1B The kinetic model of gases 1B.1 (a) 493 m s βˆ’1 (b) 615 m s βˆ’1 1B.2 (a) mean (79 K) = 647 m s βˆ’1 mean (315 K) = 1.29 km s βˆ’1 mean (1500 K) = 2.82 km s βˆ’1 (b) mean (79 K) = 323 m s βˆ’1 mean (315 K) = 645 m s βˆ’1 mean (1500 K) = 1.41 km s βˆ’1 1B.3 3.72 1B.4 N 2 0.80 g He 0.30 g 1B.5 65 mPa 1B.6 = 0.97 ΞΌm = 120 Γ— 10 3 1B.7 (a) 7.0 Γ— 10 10 (b) 7.0 Γ— 10 8 (c) 7.0 Γ— 10 4 1B.9 (a) 6.8 nm (b) 68 nm (c) 6.8 mm Topic 1C Real gases 1C.1 c = 0.242 1C.2 CH 4 c = 0.288 C 2 H 6 c = 0.274 C 3 H 8 c = 0.276 1C.3 2.15 MPa 1C.4 βˆ’3.37 Γ— 10 βˆ’5 m 3 mol βˆ’1 1C.5 βˆ’3.49 Γ— 10 βˆ’8 Pa βˆ’1 1C.6 (a) (i) 101 kPa (ii) 83.1 MPa (b) (i) 101 kPa (ii) 206 MPa 1C.7 βˆ’0.608 MPa 1C.8 = 4.6 Γ— 10 βˆ’5 m 3 mol βˆ’1 = 0.66 1C.9 1842 K Answers to problems 1.1 0.50 m 3 1.2 28.82 g mol βˆ’1 130 kg 1.3 6.8 kPa 1.4 713 Torr 1.5 N 2 = 0.7809 O 2 = 0.2094 Ar = 0.0098 1.6 132 g mol βˆ’1 1.7 16.4 g mol βˆ’1
Transcript
Page 1: The properties of gases

Atkins & de Paula: Elements of Physical Chemistry, Seventh Edition

ANSWERS TO END OF CHAPTER EXERCISES

1

Focus 1

The properties of gases

Answers to exercises

Topic 1A The perfect gas

1A.1 (a) 810 Torr

(b) 0.962 atm

(c) 0.222 atm

(d) 1.03 Γ— 105 Pa

1A.2 92 kPa

1A.3 2.25 kPa

1A.4 4.33 mmol

1A.5 660 bar

1A.6 10.0 atm

1A.7 418 kPa

1A.8 173 kPa

1A.9 βˆ’243.6 ℃

1A.10 394 K

1A.11 (a) 3.6 m3

(b) 178 m3

1A.12 3.4 Γ— 105 m3

1A.13 benzene 0.355, toluene 0.645

1A.14 (a) 1.32 Γ— 10βˆ’3m3

(b) 61.2 Γ— 103 Pa

Topic 1B The kinetic model of gases

1B.1 (a) 493 m sβˆ’1

(b) 615 m sβˆ’1

1B.2 (a) 𝑣mean(79 K) = 647 m sβˆ’1

𝑣mean(315 K) = 1.29 km sβˆ’1

𝑣mean(1500 K) = 2.82 km sβˆ’1

(b) 𝑣mean(79 K) = 323 m sβˆ’1

𝑣mean(315 K) = 645 m sβˆ’1

𝑣mean(1500 K) = 1.41 km sβˆ’1

1B.3 3.72

1B.4 π‘šN2 0.80 g

π‘šHe 0.30 g

1B.5 65 mPa

1B.6 πœ† = 0.97 ΞΌm

𝑁 = 120 Γ— 103

1B.7 (a) 7.0 Γ— 1010

(b) 7.0 Γ— 108

(c) 7.0 Γ— 104

1B.9 (a) 6.8 nm

(b) 68 nm

(c) 6.8 mm

Topic 1C Real gases

1C.1 𝑍c = 0.242

1C.2 CH4 𝑍c = 0.288

C2H6 𝑍c = 0.274

C3H8 𝑍c = 0.276

1C.3 2.15 MPa

1C.4 βˆ’3.37 Γ— 10βˆ’5 m3molβˆ’1

1C.5 βˆ’3.49 Γ— 10βˆ’8 Paβˆ’1

1C.6 (a) (i) 101 kPa

(ii) 83.1 MPa

(b) (i) 101 kPa

(ii) 206 MPa

1C.7 βˆ’0.608 MPa

1C.8 𝑏 = 4.6 Γ— 10βˆ’5 m3 molβˆ’1

𝑍 = 0.66

1C.9 1842 K

Answers to problems

1.1 0.50 m3

1.2 28.82 g molβˆ’1

130 kg

1.3 6.8 kPa

1.4 713 Torr

1.5 π‘₯N2= 0.7809

π‘₯O2= 0.2094

π‘₯Ar = 0.0098

1.6 132 g molβˆ’1

1.7 16.4 g molβˆ’1

Page 2: The properties of gases

Atkins & de Paula: Elements of Physical Chemistry, Seventh Edition

ANSWERS TO END OF CHAPTER EXERCISES

2

1.8 (a) 𝑝H2= 200 kPa

𝑝N2= 100 kPa

(b) 300 kPa

1.9 (a) 72 K

(b) 943 m sβˆ’1

1.10 1.0 Γ— 1013 sβˆ’1

1.11 0.57 dm3 molβˆ’1

1.12 π‘Ž = 0.656 Pa m6molβˆ’2

𝑏 = 5.54 Γ— 10βˆ’5 m3 molβˆ’1

1.13 π‘Ž = 0.321 Pa m6 molβˆ’2

𝑏 = 6.50 Γ— 10βˆ’5 m3molβˆ’1

π‘Ÿ = 1.86 Γ— 10βˆ’10 m

1.14 π‘Ž = 𝟎. πŸπŸπŸ– 𝐏𝐚 π¦πŸ” 𝐦𝐨π₯βˆ’πŸ

𝑏 = πŸ‘. πŸ“ Γ— πŸπŸŽβˆ’πŸ“π¦πŸ‘ 𝐦𝐨π₯βˆ’πŸ

Answers to projects

1.1 (d) 𝑓 β‰ˆ 10βˆ’2

1.2 (a) 720 Mbar

(d) 0.21 Mbar

(e) 0.029 Mbar

1.3 (c) 1030 K

1.4 (c) 𝑝c = 101.3 bar

𝑉c = 0.1327 dm3 molβˆ’1

𝑇c = 431.3 K

Focus 2

The First Law of thermodynamics

Answers to exercises

Topic 2A Work

2A.1 (a) 𝑀expansion = βˆ’0.10 J

(b) 𝑀expansion = βˆ’100 J

(a) 𝑀compression = +0.10 J

(b) 𝑀compression = +100 J

2A.2 βˆ’5.5 kJ

2A.3 (a) βˆ’99 J

(b) βˆ’167 J

2A.4 +123 J

2A.5 +29.9 J

2A.6 βˆ’1.25 kJ

2A.7 (a) 0

(b) βˆ’783 J

2A.8 βˆ’100 J

Topic 2B Heat

2B.1 23.7 J Kβˆ’1

2B.2 (a) 27 J Kβˆ’1

(b) 0.45 J Kβˆ’1gβˆ’1

(c) 25 J Kβˆ’1molβˆ’1

2B.3 42 kJ

2B.4 87 kJ

2B.5 𝐢𝑉,m = 29.9 J Kβˆ’1molβˆ’1

𝐢𝑝,m = 38.2 J Kβˆ’1molβˆ’1

Topic 2C Internal energy

2C.1 βˆ’41 kJ

2C.2 +42.5 J

Topic 2D Enthalpy

2D.1 +20 kJ

2D.2 0

2D.3 (a) exothermic

(b) endothermic

(c) endothermic

(d) endothermic

(e) endothermic

2D.4 Δ𝐻 = π‘žπ‘ = βˆ’1.2 kJ

𝐢𝑝 = 80 J Kβˆ’1

2D.5 Δ𝐻 = π‘žπ‘ = +2.2 kJ

Ξ”π‘ˆ = +1.6 kJ

2D.6 28.25 J Kβˆ’1molβˆ’1

Topic 2E Physical change

2E.1 1740 kJ molβˆ’1

2E.2 19.5 kJ molβˆ’1

2E.3 +492 kJ molβˆ’1

2E.4 +2.83 Γ— 104 kJ

Page 3: The properties of gases

Atkins & de Paula: Elements of Physical Chemistry, Seventh Edition

ANSWERS TO END OF CHAPTER EXERCISES

3

2E.5 (a) +2.44 kJ molβˆ’1

(b) +2.26 kJ molβˆ’1

2E.6 +93 kJ molβˆ’1

2E.7 π‘žπ‘ = Δ𝐻 = +80.0 kJ

𝑀 = βˆ’5.20 kJ

Ξ”π‘ˆ = +74.8 kJ

2E.8 2.58 kJ molβˆ’1

2E.9 +239 kJ molβˆ’1

Topic 2F Chemical change

2F.1 βˆ’124 kJ molβˆ’1

2F.2 (a) 388 kJ molβˆ’1

(b) smaller

(c) Ξ”f𝐻o βˆ’ 38 kJ molβˆ’1

2F.3 398 kJ molβˆ’1

2F.4 (a) +16 kJ molβˆ’1

(b) βˆ’772 kJ molβˆ’1

2F.5 (a) βˆ’1560 kJ molβˆ’1

(b) +51.88 kJ gβˆ’1

(c) methane: +55.5 kJ gβˆ’1

ethane is less exothermic

2F.6 βˆ’4564.7 kJ molβˆ’1

2F.7 βˆ’85 kJ molβˆ’1

2F.8 (a) βˆ’3290 kJ

(b) βˆ’2710 kJ

2F.9 βˆ’432 kJ molβˆ’1

2F.10 +225 kJ molβˆ’1

Answers to problems

2.1 +920 kJ

610 s

2.2 (a) 37 K

(b) 4.1 kg

2.3 +774 J

2.4 +1.86 kJ

2.5 (a) 175 kJ molβˆ’1

(b) 274 kJ molβˆ’1

(c) 150 kJ molβˆ’1

(d) 449 kJ molβˆ’1

2.6 +2.468 kJ molβˆ’1

2.7 (a) 20.83 J Kβˆ’1molβˆ’1

(b) (i) +641 J molβˆ’1

(ii) +458 J molβˆ’1

2.8 +39.8 kJ molβˆ’1

2.9 2.38 kJ molβˆ’1

2.10 +40.88 kJ molβˆ’1

2.11 +1152 kJ

2.12 4.22 kJ Kβˆ’1

+0.768 K

2.13 (a) βˆ’2800 kJ molβˆ’1

(b) βˆ’2800 kJ molβˆ’1

(c) βˆ’1.27 Γ— 103 kJ molβˆ’1

2.14 (a) βˆ’1333 kJ molβˆ’1

(b) βˆ’1331 kJ molβˆ’1

(c) βˆ’815 kJ molβˆ’1

2.15 +112.27 kJ molβˆ’1

2.16 βˆ’382.96 kJ molβˆ’1

2.17 (a) βˆ’57.29 kJ molβˆ’1

(b) βˆ’28.6 kJ molβˆ’1

(c) βˆ’138.2 kJ molβˆ’1

(d) βˆ’32.88 kJ molβˆ’1

(e) βˆ’55.84 kJ molβˆ’1

2.19 (a) +1.9 kJ molβˆ’1

(b) +30.6 kJ molβˆ’1

2.20 (a) βˆ’2205 kJ molβˆ’1

(b) βˆ’2200 kJ molβˆ’1

2.21 +11.3 kJ molβˆ’1

2.22 βˆ’56.98 kJ molβˆ’1

2.23 (a) decrease

(b) increase

(c) decrease

2.24 (a) increase

(b) increase

Page 4: The properties of gases

Atkins & de Paula: Elements of Physical Chemistry, Seventh Edition

ANSWERS TO END OF CHAPTER EXERCISES

4

2.25 +7.04 J molβˆ’1

Answers to projects

2.1 (a) more negative

(b) more positive

2.2 (a) 𝑀 = βˆ’π‘›π‘…(𝑇i + 𝑐𝑉i) ln(𝑉f/𝑉i) + 𝑛𝑅𝑐(𝑉f βˆ’ 𝑉i)

(b) w more negative

2.3 (a) Ξ”π‘ˆm = ΒΌπ‘Žπ‘‡4

(b) 𝐢𝑉,m = 𝑏 + 2𝑐𝑇

2.4 (a) +818 J molβˆ’1

2.6 (a) 40000 K

2.7 π‘Ž = 29.74 J Kβˆ’1molβˆ’1

𝑏 = 2.51 Γ— 10βˆ’2 J Kβˆ’2molβˆ’1

𝑐 = βˆ’1.55 Γ— 105 J K molβˆ’1

2.9 (a) 7.4 per cent

(b) 40 kJ

(c) 15 m

(d) blood temperature, 37 C

(e) 25 kJ

(f) 9.1 m

Focus 3

The Second Law of thermodynamics

Answers to exercises

Topic 3A Entropy

3A.1 (a) +1.7 J Kβˆ’1

(b) +1.2 J Kβˆ’1

3A.2 +0.41 J Kβˆ’1

3A.3 1470 K

Topic 3B Entropy changes

3B.1 +14 J Kβˆ’1molβˆ’1

3B.2 2.89 dm3

3B.3 +23.6 J Kβˆ’1

3B.4 βˆ’93.0 J Kβˆ’1

3B.5 βˆ’45.1 kJ

βˆ’165 J Kβˆ’1

3B.6 (a) +120 J Kβˆ’1

(b) βˆ’120 J Kβˆ’1

3B.7 +0.95 J Kβˆ’1molβˆ’1

3B.8 (a) +122 J Kβˆ’1

(b) +130 J Kβˆ’1

(c) +606 J Kβˆ’1

The total entropy change of the system:

+858 J Kβˆ’1

3B.9 (a) +85 J Kβˆ’1molβˆ’1

(b) +34 kJ molβˆ’1

3B.10 (a) +87.8 J Kβˆ’1molβˆ’1

(b) βˆ’87.8 J Kβˆ’1molβˆ’1

Topic 3C Absolute entropy

3C.1 6.69 mJ Kβˆ’1molβˆ’1

3C.3 +11.5 J Kβˆ’1molβˆ’1

Topic 3D The Gibbs energy

3D.1 (a) positive

(b) negative

(c) positive

3D.2 (a) βˆ’412.9 J Kβˆ’1molβˆ’1

(b) +92.6 J Kβˆ’1molβˆ’1

(c) βˆ’153.1 J Kβˆ’1molβˆ’1

(d) βˆ’21.0 J Kβˆ’1molβˆ’1

(e) +512.0 J Kβˆ’1molβˆ’1

3D.3 (a) βˆ’198.72 J Kβˆ’1 mol–1

(b) +309 J Kβˆ’1 molβˆ’1

Answers to problems

3.1 (a) +33 J Kβˆ’1

3.2 βˆ’7.9 J Kβˆ’1molβˆ’1

3.3 0.63 𝑇i

3.5 +5.1 J Kβˆ’1

3.6 +79 J Kβˆ’1molβˆ’1

3.7 (b) 4.1 Γ— 10βˆ’23 J Kβˆ’1

3.8 (c) 3.37 J Kβˆ’1 molβˆ’1

3.9 4.0 Γ— 10βˆ’4J Kβˆ’1molβˆ’1

Page 5: The properties of gases

Atkins & de Paula: Elements of Physical Chemistry, Seventh Edition

ANSWERS TO END OF CHAPTER EXERCISES

5

3.10 0.256 J Kβˆ’1molβˆ’1

3.11 +5.03 kJ Kβˆ’1

3.12 (a) βˆ’0.69 J Kβˆ’1molβˆ’1

(b) +0.14 J Kβˆ’1molβˆ’1

3.13 (a) βˆ’93 kJ molβˆ’1

(b) Yes

(c) +300 J Kβˆ’1molβˆ’1

3.14 0.41 g

3.15 +17 J

3.16 8.2 Γ— 1023molecules

Answers to projects

3.1 (a) 3.3 kW

(b) 180 kW

3.2 Δ𝑆 = π‘Ž ln(𝑇f/𝑇i) + 𝑏(𝑇f βˆ’ 𝑇i)

βˆ’Β½π‘(𝑇fβˆ’2 βˆ’ 𝑇i

βˆ’2)

3.3 (b) 2.02 Γ— 10βˆ’22 J Kβˆ’1molβˆ’1

(d) 𝑄

𝑁< 0.01

3.4 (a) Yes

(b) 0.46 mol

(c) βˆ’12 W mβˆ’3

(d) battery: βˆ’150 Γ— 103 W mβˆ’3

computer battery

Focus 4

Physical transformation

Answers to exercises

Topic 4A The thermodynamics of transition

4A.2 graphite

4A.3 No

4A.4 (a) +2.7 kJ molβˆ’1

(b) βˆ’20 kJ molβˆ’1

4A.5 +4.2 kJ molβˆ’1

4A.6 βˆ’3.5 kJ molβˆ’1

Topic 4B Phase diagrams of pure substances

4B.1 (a) 7.9 kg

(b) 15 kg

(c) 1.1 g

4B.2 0.709 atm

which is equivalent to 0.719 bar

4B.3 331 K

4B.4 758 mbar

4B.5 36.7 kJ molβˆ’1

4B.6 A: 15.15 B: unchanged

4B.7 1

4B.8 2

Topic 4C Partial molar quantities

4C.1 886.8 cm3

4C.2 96.9 cm3

4C.3 +1.8 kJ molβˆ’1

4C.4 +32.631 J molβˆ’1

4C.5 (a) βˆ’1.31 kJ molβˆ’1

(b) +4.38 J Kβˆ’1molβˆ’1

(c) spontaneous

4C.6 (a) Δ𝐺m βˆ’ 1.40 kJ molβˆ’1

Δ𝑆m + 4.71 J Kβˆ’1molβˆ’1

(b) spontaneous

4C.7 4.99 kPa

Topic 4D Solutions

4D.1 17.5 g

4D.2 8.92 Γ— 10βˆ’2 mol kgβˆ’1

4D.3 𝑐sucrose = 0.403 mol dmβˆ’3

𝑏sucrose = 0.388 mol kgβˆ’1

4D.4 1.80 Γ— 10βˆ’3

4D.5 βˆ’37 J molβˆ’1

4D.6 π‘₯CO2= 4.8 Γ— 10βˆ’3

4D.7 129 kPa

4D.8 7985 Pa

4D.9 (a) 1.3 mmol dmβˆ’3

(b) 17.0 mmol dmβˆ’3

4D.10 𝑏N2= 0.51 mmol kgβˆ’1

𝑏O2= 0.28 mmol kgβˆ’1

Page 6: The properties of gases

Atkins & de Paula: Elements of Physical Chemistry, Seventh Edition

ANSWERS TO END OF CHAPTER EXERCISES

6

4D.11 34.3 mmol dmβˆ’3

4D.12 π‘₯T = 0.93 π‘₯X =0.07

𝑦T = 0.97 𝑦X = 0.03

4D.13 +5.6 kJ molβˆ’1

Topic 4E Colligative properties

4E.1 59.1 g molβˆ’1

4E.2 +0.061 K

4E.3 +0.36 K

4E.4 207 g molβˆ’1

Topic 4F Phase diagrams of mixtures

4F.1 𝑛′

𝑛′′ = 0.31

4F.2 𝑐Eβ€² (aq) = 0.050 mol dmβˆ’3

𝑐Eβ€² (org) = 0.0075 mol dmβˆ’3

4F.3 0.25

Answers to problems

4.1 (b) 711 K

4.3 (a) βˆ’0.1346 bar Kβˆ’1

(b) +135.6 bar

4.4 (a) 31.69 kJ molβˆ’1

(b) 341.7 K

4.5 353 K

4.6 3.0 Torr

4.11 2.30 kPa

4.12 (a) 171.03 Torr

(b) 6.92 Torr

(c) 𝑦eth = 0.96111

𝑦chl = 0.03889

(d) 692 Torr

4.13 (a) 43.95 Torr

(b) 1.13 Torr

(c) 22.6 kPa

4.14 6.41 Γ— 103 kPa

4.15 A: 𝐾Hβ€² = 861 Torr

B: 𝐾Hβ€² = 1103 Torr

4.16 A: KH = 242 Torr

B: KH = 397 Torr

4.17 0.11 C

4.18 𝑀 = 88.19 kg molβˆ’1

4.19 13.9 kg molβˆ’1

4.20 (a) yT = 0.36

(b) yT = 0.81

4.21 (a) 0.150

(b) 𝑛′

𝑛′′ = 9.81

4.22 (a) 0.345

(b) 𝑛′

𝑛′′ = 0.135

4.25 (c) 5% tin by mass

(d) No Ag3Sn in the solid

(e) 20% Ag3Sn by mass

Answers to projects

4.1 (a) 6.4 kPa

(c) 5.7 kPa

4.2 (b) greater

(c) 0.69 per cent

4.3 (a) π‘₯ethanol = 0.072

(b) 53.1039 cm3 mol

-1

4.4 (a) 𝑉water/cm3 molβˆ’1 =

18.068 + 6.557 Γ— 10βˆ’3𝑏2 βˆ’ 1.018 Γ— 10βˆ’3𝑏3

4.5 (a) 4.4 cm3O2

(b) 4.0 atm: 56 ΞΌg N2,

1.0 atm: 14 ΞΌg N2

(c) 170 ΞΌg N2

Focus 5

Chemical change

Answers to exercises

Topic 5A The thermodynamics of reaction

5A.1 (a) 𝑄 = 𝑝CO2(g)

6

[CH3COCOOH]2𝑝O2(g)5 Γ— (𝑐o2/𝑝o)

Page 7: The properties of gases

Atkins & de Paula: Elements of Physical Chemistry, Seventh Edition

ANSWERS TO END OF CHAPTER EXERCISES

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(b) 𝑄 = [FeSO4]

[PbSO4]

(c) 𝑄 = [HCl]2

𝑝H2(g)Γ—

𝑝o

𝑐o2

(d) 𝑄 = [CuCl2]

[CuCl]2 Γ— 𝑐o

5A.2 +12.3 kJ molβˆ’1

5A.3 +6.8 kJ molβˆ’1

5A.4 βˆ’25.1 kJ molβˆ’1

5A.5 +26 kJ molβˆ’1

5A.7 βˆ’14.4 kJ molβˆ’1

formation of NH3

5A.8 2.31

5A.9 (a) 5.2 Γ— 1011

(b) 850

5A.10 1

5A.11 βˆ’2.42 kJ molβˆ’1

5A.12 3.01

5A.13 glucose-1-phosphate 3.4 Γ— 103

glucose-6-phosphate 2.5 Γ— 102

glucose-3-phosphate 36

Topic 5B The equilibrium constant

5B.1 𝑝CO2= 10.2 kPa

5B.2 3.3 Γ— 106

5B.3 6.94

5B.4 3.1 Γ— 10βˆ’3

5B.5 4.31 Γ— 1043

Topic 5C Response to conditions

5C.1 (a) 52.9 kJ molβˆ’1

(b) βˆ’52.9 kJ molβˆ’1

5C.2 βˆ’92.2 kJ molβˆ’1

5C.3 𝐾 = 7.23 Γ— 1011

5C.4 (a) products

(b) products

(c) reactants

(d) products

Topic 5D Proton transfer equilibria

5D.3 (a) pH = 4.8

pOH = 9. 2

(b) pH = 2.8

pOH = 11.2

(c) pH = 13.3

pOH = 0.7

(d) pH = 4.3

pOH = 9.7

5D.4 (a) 9.5 mmol dmβˆ’3

pH = 2.0

(b) 5.01 Γ— 10βˆ’13mol dmβˆ’3

pH = 12.3

(c) 53 mmol dmβˆ’3

pH = 1.3

Topic 5E Polyprotic acids

5E.1 (a) 9.7 Γ— 10βˆ’4

(b) 3.8 Γ— 10βˆ’10

5E.2 (a) 𝑓(H2S) = 1.0

𝑓(HSβˆ’) = 1.3 Γ— 10βˆ’3

𝑓(S2βˆ’) = 9.2 Γ— 10βˆ’14

undissociated (H2S) form

(b) 𝑓(H2S) = 7.7 Γ— 10βˆ’4

𝑓(HSβˆ’) = 1.0

𝑓(S2βˆ’) = 7.1 Γ— 10βˆ’5

HS– ions

Topic 5F Acid–base equilibria of salts in water

5F.1 4.36

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5F.2 (a) acidic

NH4+(aq) + H2O(l) β‡Œ H3O+(aq) + NH3(aq)

(b) basic

H2O(l) + CO32–(aq) β‡Œ HCO3

(aq) + OH–(aq)

(c) basic

H2O(l) + F– (aq) β‡Œ HF(aq) + OH–(aq)

(d) neutral

(e) acidic

[Al(H2O)6]3+(aq) + H2O(l) β‡Œ

[Al(H2O)5OH]2+(aq) + H3O+(aq)

(f) acidic

[Co(H2O)6]2+(aq) + H2O(l) β‡Œ

[Co(H2O)OH]+(aq) + H3O+(aq)

5F.3 (a) pH 2–4

(b) pH 3–5

(c) pH 11.5–13.5

(d) pH 6–8

(e) pH 5–7

5F.4 (a) H3PO4 and NaH2PO4

(b) NaH2PO4 and Na2HPO4, or

NaHSO3 and Na2SO3

Topic 5G Solubility equilibria

5G.2 (a) 1.0 Γ— 10βˆ’5 mol dmβˆ’3

(b) 1.2 Γ— 10βˆ’4 mol dmβˆ’3

(c) 9.3 Γ— 10βˆ’11 mol dmβˆ’3

(d) 6.9 Γ— 10βˆ’7 mol dmβˆ’3

5G.3 (a) 5.5 Γ— 10βˆ’10mol dmβˆ’3

(b) 3.2 Γ— 10βˆ’3 mol dmβˆ’3

(c) 1.6 Γ— 10βˆ’7 mol dmβˆ’3

(d) 2.5 Γ— 10βˆ’7 mol dmβˆ’3

Topic 5H Ions in solution

5H.1 1.35

5H.3 7.63 mS m2molβˆ’1

5H.4 347 ΞΌm sβˆ’1

Topic 5I Electrochemical cells

5I.2 (a) 𝑣 = 2

(b) 𝑣 = 2

(c) 𝑣 = 4

(d) 𝑣 = 2

(e) 𝑣 = 2

(f) 𝑣 = 1

5I.3 βˆ’212 kJ molβˆ’1

5I.4 +7.7 kJ molβˆ’1

Topic 5J Standard potentials

5J.1 Exercise 5I.1

(a) 0

(b) 0

(c) +0.87 V

(d) βˆ’0.27 V

(e) βˆ’0.62 V

(f) +1.67 V

Exercise 5I.2

(a) +0.08 V

(b) +0.27 V

(c) +1.23 V

(d) +0.695 V

(e) +0.54 V

(f) +0.37 V

5J.2 πΈβŠ• = +1.14 V

Ξ”rπΊβŠ• = βˆ’440 kJ molβˆ’1

5J.3 110

5J.4 0.320 V

Answers to problems

5.1 (a) βˆ’91.14 kJ molβˆ’1

(b) +594.6 kJ molβˆ’1

(c) βˆ’66.8 kJ molβˆ’1

(d) +99.8 kJ molβˆ’1

(e) βˆ’415.80 kJ molβˆ’1

5.2 +279 kJ molβˆ’1

5.3 (a) βˆ’32 kJ molβˆ’1

(b) (i) βˆ’49 kJ molβˆ’1

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(ii) βˆ’67 kJ molβˆ’1

5.4 βˆ’0.7 kJ molβˆ’1

5.5 (a) exergonic

(b) endergonic

(c) endergonic

(d) exergonic

5.6 (a) 1120 K

(b) 397 K

5.7 1500 K

5.8 (a) K > 1

(b) K < 1

(c) K > 1

(d) K > 1

(e) K > 1

5.10 𝐾r1/𝐾r2 = 1.4 Γ— 1046

5.11 βˆ’245 kJ molβˆ’1

5.12 0.0958, 0.9042

5.13 𝑝NH3(g) = 1.93 bar

𝑝H3(g) = 1.10 bar

𝑝N3(g) = 0.03 bar

5.14 2.7 Γ— 10βˆ’4bar

5.15 (a) ⌈PCl5βŒ‰ = 0.016 mol dmβˆ’3

[PCl3] = [Cl2] = 0.013 mol dmβˆ’3

(b) 45 per cent

5.16 𝑝H2(g) β‰ˆ 0.20 bar

𝑝N2(g) β‰ˆ 0.20 bar

𝑝NH3(g) = 7.6 Γ— 10βˆ’5 bar

5.17 +41.1 kJ molβˆ’1

5.19 (a) 9.24

(b) βˆ’12.9 kJ molβˆ’1

(c) +161 kJ molβˆ’1

(d) +248 J Kβˆ’1molβˆ’1

5.20 βˆ’187.78 kJ molβˆ’1

5.21 (a) +12.50 kJ molβˆ’1

(b) +9.05 kJ molβˆ’1

(c) βˆ’8.6 J Kβˆ’1molβˆ’1

5.22 (a) [H3O+] = 1.6 Γ— 10βˆ’7 mol dmβˆ’3

pH = 6.8

(b) [OHβˆ’] = 1.6 Γ— 10βˆ’7 mol dmβˆ’3

pOH = 6.8

5.23 (a) 2 D2O(l) β‡Œ D3O+(aq) + OD

–(aq)

(b) 14.9

(c) 3.67 Γ— 10βˆ’8 mol dmβˆ’3

(d) 7.43

(e) pD + pOD = p𝐾w = 14.9

5.24 ideal: pH = 0.30

𝛾H3O+ = 0.769: pH = 0.42

5.26 +57.2 kJ molβˆ’1

πŸ“.28 p𝐾a = 8.02

5.29 (a) 5 per cent

(b) 0.34 per cent

(c) 2.4 per cent

5.30 (a) pH = 1.94

pOH = 12.1

7.4 per cent

(b) pH = 3.7

pOH = 10.3

81 per cent

(c) pH = 0.84

pOH = 13.16

58 per cent

5.31 (a) pH = 6.6

(b) pH = 2.1

(c) pH = 1.5

5.32 [(COOH)2] = 0.08 mol dmβˆ’3

[HOOCCO2βˆ’] = 0.07 mol dmβˆ’3

[(CO2)22βˆ’] = 6.5 Γ— 10βˆ’5 mol dmβˆ’3

[H3O+] = 0.07 mol dmβˆ’3

[OHβˆ’] = 1.4 Γ— 10βˆ’13 mol dmβˆ’3

5.33 [H2S] = 0.065 mol dmβˆ’3

[HSβˆ’] = 9.2 Γ— 10βˆ’5mol dmβˆ’3

[S2βˆ’] = 7.1 Γ— 10βˆ’15mol dmβˆ’3

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[H3O+] = 9.2 Γ— 10βˆ’5mol dmβˆ’3

[OHβˆ’] = 1.1 Γ— 10βˆ’10 mol dmβˆ’3

πŸ“.35 pH = 9.2

5.36 pH = 4.8

5.38 (a) [acid]

[base]= 1.6 Γ— 10βˆ’5

(b) [acid]

[base]= 1

(c) [acid]

[base]= 5.0

5.40 pH = 2.71

5.41 (a) pH = 5.1

(b) pH = 9.1

(c) pH = 2.7

5.42 (a) pH = 2.9

(b) pH = 4.6

(c) 12.5 cm3

(d) pH = 4.75

(e) 25.0 cm3

(f) pH = 8.72

5.43 𝐾a = 6.92 Γ— 10βˆ’6

pKa = 5.16

pH = 3.38

5.44 8.00

5.46 (a) pKa = 3.08

𝐾a = 8.32 Γ— 10βˆ’4

(b) pH = 2.78

5.47 pH = 8.3

5.48 (a) pH = 4.75

(b) pH = 5.0

(c) pH = 4.1

5.49 Ξ”s𝐺o = +241 kJ molβˆ’1

5.50 𝑠 = 1.25 Γ— 10βˆ’5 mol dmβˆ’3

5.51 (b) increase

5.52 (a) 2.73 g

(b) 2.92 g

5.53 0.015 mol kgβˆ’1 MgF2

𝛾±,MgF2= 0.538

π‘ŽMg2+ = 0.0081

π‘ŽFβˆ’ = 0.016

0.025 mol kgβˆ’1 NaCl

𝛾±,NaCl = 0.733

π‘ŽNa+ = 0.018

π‘ŽClβˆ’ = 0.018

5.54 𝐡 = 2.022

5.55 13.83 mS m2molβˆ’1

5.56 (a) 12.6 mS m2 molβˆ’1

(b) 210 S mol1/2m1/2

5.57 1.364 Γ— 10βˆ’5 mol dmβˆ’3

5.58 3.70

5.59 4.85

5.60 +28 mV

5.61 βˆ’1.18 V

5.62 (a) +1.23 V

(b) +1.11 V

5.63 (a) right-hand

(b) +1.06 V

5.64 (a) βˆ’1.20 V

(b) βˆ’ 1.19 V

5.65 (a) βˆ’394 kJ molβˆ’1

(b) βˆ’787 kJ molβˆ’1

(c) +75 kJ molβˆ’1

(d) βˆ’284 kJ molβˆ’1

(e) βˆ’291 kJ molβˆ’1

(f) +498 kJ molβˆ’1

5.66 (a) 𝐸cello = βˆ’0.46 V

Ξ”r𝐺o = +88.8 kJ molβˆ’1

Ξ”r𝐻o = +146.39 kJ molβˆ’1

(b) +86.9 kJ molβˆ’1

5.67 (a) 𝐸cello = +1.57 V

Ξ”r𝐺o = βˆ’606 kJ molβˆ’1

(b) βˆ’604 kJ molβˆ’1

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5.70 (a) βˆ’40 kJ molβˆ’1

(b) +29.7 kJ molβˆ’1

(c) βˆ’313 kJ molβˆ’1

5.71 (a) +0.324 V

(b) +0.45 V

5.72 +0.56 V

5.73 (a) 6.4 Γ— 109

(b) 1.3 Γ— 107

(c) 9.4 Γ— 1043

(d) 1.1 Γ— 1025

(e) 8.2 Γ— 10βˆ’7

(f) 3.4 Γ— 1013

5.75 (a) +0.94 V

(b) {1.51 + 0.041 Γ— ln(10βˆ’pH)} V

5.76 +0.22 V

5.77 (a) βˆ’0.6119 V

(b) βˆ’0.22 V

(d) +0.41 V

(e) p𝐾a = 10.28

5.79 Ξ”r𝑆o = βˆ’324 J Kβˆ’1molβˆ’1

Ξ”r𝐻o = βˆ’571 kJ molβˆ’1

Answers to projects

5.3 (b) +0.2234 V

5.4 (b) +0.206 V

Focus 6

Chemical kinetics

Answers to exercises

Topic 6A Empirical chemical kinetics

6A.1 1.2 mmol dmβˆ’3

6A.2 A: 1.6 mol dmβˆ’3sβˆ’1

B: 0.80 mol dmβˆ’3sβˆ’1

D: 2.4 mol dmβˆ’3sβˆ’1

6A.3 0.80 mol dmβˆ’3sβˆ’1

Topic 6B Rate laws

6B.1 molβˆ’2dm6 sβˆ’1

6B.2 π‘˜r1: molβˆ’1dm3sβˆ’1

π‘˜r2: molβˆ’1dm3

6B.3 π‘˜r1: kPaβˆ’1/2sβˆ’1

π‘˜r2: dimensionless

6B.4 3.7 Γ— 106 dm3mol–1s–1

Topic 6C Integrated rate laws

6C.1 1.58 Γ— 10βˆ’3 sβˆ’1

6C.2 1.12 Γ— 10βˆ’4sβˆ’1

6C.5 (a) 14 Pa sβˆ’1

(b) 1.5 Γ— 103s

6C.7 1326 s

6C.8 3100 a

6C.9 (a) 0.63 ΞΌg

(b) 0.16 ΞΌg

6C.10 (a) 0.138 mol dmβˆ’3

(b) 0.095 mol dmβˆ’3

6C.11 13.6 s

6C.12 𝑑1/2 = 5.70 h

(a) 78.4 kPa

(b) 77.6 kPa

Topic 6D The temperature dependence of

reaction rates

6D.1 7.5 Γ— 10βˆ’14molβˆ’1dm3sβˆ’1

6D.2 (a) 1.86 Γ— 1023a

(b) 75.8 s

6D.3 𝐴 = 1.37 Γ— 1015dm3molβˆ’1sβˆ’1

6D.4 298.86 K

6D.5 52 kJ mol1

6D.6 35.9 kJ molβˆ’1

6D.7 121 kJ molβˆ’1

6D.8 βˆ’21.6 kJ molβˆ’1

6D.9 (a) 27.2 kJ molβˆ’1

(b) 54.3 kJ molβˆ’1

6D.10 𝐴 = 1.44 Γ— 1012 molβˆ’1 dm3 sβˆ’1

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6D.11 0.8 nm2

Topic 6E The approach to equilibrium

6E.1 7.5 Γ— 105 sβˆ’1

6E.2 23.8 msβˆ’1

6E.3 21 ms

Topic 6F Reaction mechanisms

6F.1 39.1 d

6F.2 increase

6F.3 1.89 Γ— 10βˆ’6 Paβˆ’1sβˆ’1

Topic 6G Reactions in solution

6G.1 (a) 6.61 Γ— 106 m3molβˆ’1sβˆ’1

(b) 3.0 Γ— 107 m3molβˆ’1sβˆ’1

6G.2 (a) βˆ’3.1 Γ— 1016 mol mβˆ’2sβˆ’1

(b) 1.6 Γ— 10βˆ’11mol

6G.3 (a) 27 h

(b) 2.7 Γ— 103 h

(c) 3.0 Γ— 103 a

6G.4 𝑁 = 1 Γ— 106

6G.5 17 kJ molβˆ’1

Topic 6H Homogeneous catalysis

6H.1 5.6 Γ— 1022

6H.2 1.62 mmol dmβˆ’3

6H.3 π‘˜cat = 1.18 Γ— 105 sβˆ’1

πœ‚ = 7.9 Γ— 106 molβˆ’1dm3sβˆ’1

Topic 6I Heterogeneous catalysis

6I.1 172 m2

6I.2 (a) 60 Pa

(b) 4.9 kPa

6I.3 (a) 0.068

(b) 0.42

Answers to problems

6.1 (a) first order

(b) 4.977 s1

6.2 (a) complex: first order

Y: second order

(b) 1.9 mol1

dm3 s1

6.3 (a) 𝑣 = π‘˜π‘Ÿ[ICl][H2]

(b) kr = 0.162 mol1

dm3 s1

(c) 20.6 Γ— 10βˆ’7mol dmβˆ’3sβˆ’1

6.4 0.248 s1

6.5

(a) second order

(b) 7.80 Γ— 10βˆ’3

dm3 mol

βˆ’1 s

βˆ’1

6.6 (a) second order

(b) 1.32 dm3 mol

–1 s

–1

6.9 second order

0.287 molβˆ’1dm3minβˆ’1

6.10 𝐸a = 272 kJ molβˆ’1

6.11 𝐸a = 180 kJ molβˆ’1

A = 2.11 mol–1

dm3 s

–1

6.12

(a) 𝑓(20 ℃) = 1.7 Γ— 10βˆ’20

(b) 𝑓(200 ℃) = 5.6 Γ— 10βˆ’13

𝐴 = 3 Γ— 1011 molβˆ’1dm3sβˆ’1

6.13 (a) 126 kJ molβˆ’1

(b) Δ𝑆‑ = 0

6.15 π‘˜r,eff = 7.12 Γ— 105 sβˆ’1

π‘˜rβ€² = 4.00 Γ— 1010 molβˆ’1 dm3sβˆ’1

6.16 {π‘˜b(π‘˜a/π‘˜aβ€² )1/2}[A2]1/2[B]

6.19 (a) 3 ClO(aq) ClO3(aq) + 2 Cl(aq)

(b) first step

6.26 𝐾M = 1.11 ΞΌmol dmβˆ’3

𝑣max = 2.31 ΞΌmol dm–3 sβˆ’1

π‘˜cat = 1.2 Γ— 102 sβˆ’1

6.27 𝐾M = 87 mmol dmβˆ’3

𝑣max = 16 ΞΌmol dm–3 sβˆ’1

6.28 𝛼 = 2.809 Paβˆ’1

π‘‰βˆž = 0.5659 cm3

6.29 gold: zeroth order

Platinum: first order

6.33 𝑐 = 165

𝑉mon = 13.1 cm3

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Answers to projects

6.1 (a) 1

[A]0βˆ’[B]0ln (

[B]/[B]0

[A]/[A]0) = π‘˜r𝑑

(b) 1

[A]βˆ’

1

[A]0= π‘˜r𝑑

6.2 (b) 𝐸a = 105.1 kJ molβˆ’1

Ξ”r𝐺o = βˆ’26.6 kJ molβˆ’1

Ξ”r𝐻o = βˆ’34.3 kJ molβˆ’1

6.6 (a) 𝐾M = 24.9 mmol dmβˆ’3

𝑣max = 4.80 mol dmβˆ’3sβˆ’1

(b) 𝐾M = 25.0 mmol dmβˆ’3

𝑣max = 4.81 mol dmβˆ’3sβˆ’1

(c) 𝐾M = 25.0 mmol dmβˆ’3

𝑣max = 4.80 molβˆ’1 dm3sβˆ’1

Focus 7

Quantum theory

Answers to exercises

Topic 7A The emergence of quantum theory

7A.1 3.05 Γ— 10βˆ’19 J

7A.2 8.226 Γ— 104 cmβˆ’1

7A.3 (a) 6.6 Γ— 10βˆ’19 J

4.0 Γ— 102 kJ molβˆ’1

(b) 3.3 Γ— 10βˆ’20 J

20 kJ molβˆ’1

(c) 1.3 Γ— 10βˆ’33 J

7.8 Γ— 10βˆ’13 kJ molβˆ’1

7A.4 (a) 𝐸(750 nm) = 2.65 Γ— 10βˆ’19 J

(b) 𝜈(250 nm) = 9.96 Γ— 105 m sβˆ’1

7A.5 (a) 6.6 Γ— 10βˆ’31m

(b) 6.6 Γ— 10βˆ’39 m

(c) 99.7 pm

7A.6 1.3 Γ— 106 m sβˆ’1

7A.7 4 Γ— 10βˆ’36m

7A.8 (a) 1.10 Γ— 10βˆ’27 kg m sβˆ’1

(b) 9.5 Γ— 10βˆ’24 kg m sβˆ’1

(c) 3.31 Γ— 10βˆ’36 kg m sβˆ’1

7A.9 2.2 Γ— 10βˆ’24 m sβˆ’1

Topic 7B The dynamics of microscopic systems

7B.1 Ξ”π‘₯ β‰₯ 0.900 nm

7B.2 Δ𝑣 β‰₯ 2.1 Γ— 10βˆ’29 m sβˆ’1

7B.3 Ξ”π‘₯ β‰₯ 1.1 Γ— 10βˆ’26 m

7B.4 Ξ”π‘₯ = 100 Γ— 10βˆ’12 m

Δ𝑣 β‰₯ 5.8 Γ— 105 m sβˆ’1

Topic 7C Translation

7C.1 (a) π‘₯ = 𝐿/2

(b) π‘₯ = 3𝐿/4

(c) π‘₯ = 5𝐿/6

7C.2 9.84 Γ— 10βˆ’23 J

7C.3 𝐿 = 1.00 Γ— 10βˆ’9 m

Topic 7D Rotation

7D.1 𝑛 = 0: ∞

𝑛 = 1: 628 pm

𝑛 = 2: 314 pm

7D.2 (a) 4.34 Γ— 10βˆ’47 kg m2

(b) 1.55 mm

7D.3 6

7D.4 ml = –4, –3, –2, –1, 0, +1, +2, +3

7D.5 6.65 Γ— 10βˆ’22 J

Topic 7E Vibration

7E.1 0.04 N mβˆ’1

7E.2 6.90 Γ— 1013 sβˆ’1

7E.3 7.94 Γ— 10βˆ’6 N mβˆ’1

Answers to problems

7.1 2.52 eV

7.2 (a) 1.23 nm

(b) 38.8 pm

(c) 3.88 pm

7.3 (a) 6.1 Γ— 10βˆ’4 N

(b) 6.1 Γ— 10βˆ’10 Pa

(c) 1600 s

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7.5 π‘₯ = Β±0.5887/π‘Ž1/2

7.7 (a) 1.8 Γ— 10βˆ’4

(b) 5.9 Γ— 10βˆ’5

7.8 5h2 / 8mL

2: (1,4) (2,2)

5h2 / 4mL

2: (1,6) (3,2)

7.9 𝐿/4 , 3𝐿/4

7.10 (a) 2.2 Γ— 10βˆ’20 J

(b) 9.2 ΞΌm

7.12 (a) 0.22

(b) 9.5 Γ— 10βˆ’3

7.13 8.79 Γ— 1011sβˆ’1

7.14 2.10 Γ— 10βˆ’22 J

7.15 0.707

Answers to projects

7.1 (a) π‘₯ = 0.1 to π‘₯ = 0.2 nm:

𝑃(π‘₯) = 1.84 Γ— 10βˆ’4, 3.8 per cent

x = 4.9 to x = 5.2 nm:

𝑃(π‘₯) = 2.36 Γ— 10βˆ’4, 74.9 per cent

(b) 0.196

(c) 0.609

(d) 0.196

7.2 (a) (i) πœ“(π‘₯) = (π‘Ž/Ο€)1/4eβˆ’π‘Žπ‘₯2/2

(ii) x = 0

(b) (i) πœ“(π‘₯) = (4π‘Ž3/Ο€)1/4π‘₯eβˆ’π‘Žπ‘₯2/2

(ii) x = Β±1/a1/2

7.3 (a) 6.432 Γ— 1013 sβˆ’1

(b) 2146 cmβˆ’1

(c) 𝜈 C13 O16 2098 cmβˆ’1

𝜈 C12 O18 2094 cmβˆ’1

𝜈 C13 O18 2045 cmβˆ’1

Focus 8

Atomic structure

Answers to exercises

Topic 8A Hydrogenic atoms

8A.1 4.10296 Γ— 10βˆ’5cm = 410.296 nm

8A.2 𝑛2 = 5

8A.3 𝑛2 = 6

8A.4 1.00047

8A.5 27 cmβˆ’1

8A.6 n1 = 2 n2 = 4

8A.7 16

8A.8 (a) 0, 0 angular node, 0 radial nodes

(b) 0, 0 angular node, 2 radial nodes

(c) 61/2ℏ, 2 angular nodes,

0 radial nodes

(d) 21/2ℏ, 1 angular node, 0 radial nodes

(e) 21/2ℏ, 1 angular node, 1 radial node

8A.9 (a) 1

(b) 9

(c) 49

8A.10 (a) 2

(b) 14

(c) 22

8A.11 0, 180, 90, 270

8A.12 (a) (𝑛 𝑙 1)

(b) l

(c) (𝑛 1)

Topic 8B Many-electron atoms

8B.2 (a) [He]2s2p3

(b) [Ar]3d2

(c) [Ar]3d5

Topic 8C Periodic trends of atomic properties

8C.2 349 kJ molβˆ’1

Topic 8D Atomic spectroscopy

8D.1 (b), (c), (e)

8D.3 nd, ng

8D.4 (a) 𝐿 = 2, 1, 0

(b) 𝐿 = 4,3, 2, 1, 0

8D.5 S = 2, 1, 0

8D.6 (a) 1S0

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(b) 3F4,

3F3,

3F2

(c) 5S2

(d) 5P3, 5P2,

5P1

8D.7 3F,

1F,

3D,

1D,

3P,

1P

8D.8 (a) 3F term,

the lowest level:

3F2

(b) 5

8D.9 [Ar]3d1

𝐽 = 5/2, 3/2

2D3/2, lowest in energy

8D.10 3F2

8D.11 Al: 2P1/2

Cl: 2P3/2

8D.12 (a), (c)

Answers to problems

8.1 n = 3 2: He3 + 15238.6 cmβˆ’1

He4 + 15239.3 cmβˆ’1

n = 2 1: He3 + 82288.5 cmβˆ’1

He4 + 82292.3 cmβˆ’1

8.2 122.31 eV

8.3 (a) n = 7 6 12368 nm

n = ∞ 6 3282 nm

(b) n = 8 6 7503 nm

n = 9 6 5908 nm

(c) 12368 nm

8.4 (a) 397.13 nm

(b) 3.400 eV

8.5 (a) 109740 cmβˆ’1

(b) n = 3 2 137170 cmβˆ’1

n = 4 2 185180 cmβˆ’1

(c) 122.5 eV

8.6 14.0 eV

8.7 0.602 π‘Ž0

8.8 (a) 0.262 a0, 2.530 a0

(b) 0.090 a0, 3.845 a0

8.9 (a) 1.4 Γ— 10βˆ’5

(b) 1.1 Γ— 10βˆ’4

8.10 (a) 1.9 π‘Ž0 , 7.10 π‘Ž0

(b) 1.87 π‘Ž0, 6.61 π‘Ž0, 15.5 π‘Ž0

8.11 Fe2+

8.12 2.142 meV

Answers to projects

8.1 (a) π‘Ÿ = π‘Ž0

(b) (i) 2.69 Γ— 10βˆ’7

(ii) 2.47 Γ— 10βˆ’8

(iii) 0

(c) 5.24 a0

(d) 5.236 π‘Ž0

8.3 (a) receding, 338 km sβˆ’1

Focus 9

The chemical bond

Answers to exercises

Topic 9A Valence bond theory

9A.1 1870 kJ molβˆ’1

9A.2 πœ“Cβˆ’H = πœ“C(1)πœ“H(2) + πœ“C(2)πœ“H(1)

9A.3 πœ“1(Οƒ-bond) =

πœ“2p𝑧A(1)πœ“2p𝑧B(2) + πœ“2p𝑧A(2)πœ“2p𝑧B(1)

πœ“2(Ο€-bond) =

πœ“2pπ‘₯A(1)πœ“2pπ‘₯B(2) + πœ“2pπ‘₯A(2)πœ“2pπ‘₯B(1)

πœ“3(Ο€-bond) =

πœ“2p𝑦A(1)πœ“2p𝑦B(2) + πœ“2pyA(2)πœ“2p𝑦B(1)

9A.5 210 times

9B.2 F2βˆ’: Β½

F2: 1

F2+: 1Β½

9B.3 O2+: 2Β½

O2: 2

O2βˆ’: 1Β½

O22βˆ’: 1

O2+ < O2 < O2

– < O2

2–

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9B.4

(a) H2βˆ’: 1Οƒg

21Οƒu1

(b) Li2: 1Οƒg2

(c) Be2: 1Οƒg2 1Οƒu

2

(d) C2: 1Οƒg2 1Οƒu

2 1Ο€u4

(e) N2: 1Οƒg2 1Οƒu

2 2Οƒg2 1Ο€u

4

(f) O2: 1Οƒg2 1Οƒu

2 2Οƒg2 1Ο€u

4 1Ο€g 2

9B.5 C2 stronger

9B.6 32 molecular orbitals

Topic 9C Molecular orbital theory:

heteronuclear diatomics

9C.1 (a) nonpolar

(b) polarized

9C.2 (a) C2, CN

(b) NO, O2, F2

9C.3 N2 is shorter

Topic 9D Molecular orbital theory:

polyatomic molecules

9D.1 βˆ’6.26 eV

604 kJ molβˆ’1

πŸ—πƒ.2 6𝛼 + 8𝛽

9D.3 0

9D.4 (a) βˆ’2𝛽

(b) βˆ’1.24𝛽

(c) βˆ’2𝛽

Answers to problems

9.2 bond angle for SO2 is 120

9.8 CO: 1Οƒ2 2Οƒ2 3Οƒ2 1Ο€4

NO: 1Οƒ2 2Οƒ2 3Οƒ2 1Ο€4 2Ο€1

CNβˆ’: 1Οƒ2 2Οƒ2 3Οƒ2 1Ο€4

9.9 XeF+ will have a shorter bond length than

XeF

9.11 1u

2g (two)

3u (two)

4g

9.12 (a) 6.00 eV

(b) 2.70 eV

9.13 (a) ethene βˆ’30750 cmβˆ’1

butadiene βˆ’37280 cmβˆ’1

hexatriene βˆ’44660 cmβˆ’1

octatetraene βˆ’47370 cmβˆ’1

(b) βˆ’71910 cmβˆ’1

9.14 (a) benzene: 𝛼 + 2𝛽, 𝛼 + 𝛽,

𝛼 + 𝛽, 𝛼 βˆ’ 𝛽, 𝛼 βˆ’ 𝛽, 𝛼 βˆ’ 2𝛽

Cyclooctatetraene:

𝛼 + 2𝛽, 𝛼 + √2𝛽, 𝛼 + √2𝛽,

𝛼, 𝛼, 𝛼 βˆ’ √2𝛽, 𝛼 βˆ’ √2𝛽, 𝛼 βˆ’ 2𝛽

(b) benzene: 2𝛽

hexatriene: 0.988𝛽

(c) cyclooctatetraene: 1.657𝛽

octatetraene: 1.516𝛽

9.15 𝛼 + √2𝛽: bonding

𝛼: non βˆ’ bonding

𝛼 βˆ’ √2𝛽: antibonding

9.16 (a) C6H6βˆ’: 1Ο€u

2 2Ο€g4 1Ο€u

1

7𝛼 + 7𝛽

(b) C6H6+: 1Ο€u

2 2Ο€g3

5𝛼 + 7𝛽

Answers to projects

9.2 (c) Ο€/4, βˆ’Ο€/4

9.3 (b) (𝑅/π‘Ž0) = 2.11

(c) πœ“1 = Β±(0.356𝐴 + 0.934𝐡)

πœ“2 = Β±(0.934𝐴 βˆ’ 0.356𝐡)

Focus 10

Molecular interactions

Answers to exercises

Topic 10A Electric properties of molecules

10A.1 βˆ’36 J molβˆ’1

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10A.2 (a) 1.78 D, 5.9 Γ— 10βˆ’30C m

(b) 0.94 D, 3.1 Γ— 10βˆ’30C m

(c) 0.76 D, 2.5 Γ— 10βˆ’30C m

10A.3 πœ‡/D = βˆ’0.89

10A.4 1.17 D

10A.5 (a) C2 m

2 J

βˆ’1

(b) (C2 m

2 J

βˆ’1) / (C

2 J

βˆ’1 m

βˆ’1) = m

3

Topic 10B Interactions between molecules

10B.1 βˆ’5.22 Γ— 10βˆ’24 J

10B.2 𝑉(π‘Ÿ) = βˆ’1.9 Γ— 10βˆ’27 J

𝑉m(π‘Ÿ) = βˆ’1.19 Γ— 10βˆ’3 J molβˆ’1

10B.3 479 pm

10B.4 π‘Ÿ = 700 pm

𝑁Aπœ– = 12.6 kJ molβˆ’1

Answers to problems

10.1 non-polar

10.2 (a) 1,2-dimethylbenzene: 0.69 D

1,3-dimethylbenzene: 0.40 D

1,4-dimethylbenzene: non-polar

(b) (i) 0.80 D

(ii) 0.40 D

(iii) non-polar

10.3 (a) 1.41 D

(b) 2.44 D

(c) 1.06 D

(d) 1.69 D

10.4 πœ‡ = 37 D

πœƒ = 11.8Β°

10.5 1.17 Γ— 10βˆ’29 C m = 3.50 D

10.7 (a) 476 kJ molβˆ’1

(b) 87.4 kJ molβˆ’1

10.9 (a) 3.72 kJ molβˆ’1

(b) βˆ’0.365 J molβˆ’1

10.10 196 pm

10.11 𝑉(π‘Ÿ) = βˆ’1.6 Γ— 10βˆ’26 J

𝑉m(π‘Ÿ) = βˆ’9.6 Γ— 10βˆ’3J molβˆ’1

𝟏𝟎.12 𝑉(π‘Ÿ) = βˆ’7.0 Γ— 10βˆ’20 J,

𝑉m(π‘Ÿ) = βˆ’42 kJ molβˆ’1

10.14 250 to 410 pm

10.16 (a) 11.6 kJ molβˆ’1

(c) 2.12 Γ— 1012 sβˆ’1

Focus 11

Molecular spectroscopy

Answers to exercises

11A.1 (a) 6.78 Γ— 1014 Hz

(b) 22600 cmβˆ’1

11A.2 (a) 2.94 Γ— 10βˆ’3 cmβˆ’1

(b) 3.41 m

11A.3 (a) 1.48 Γ— 104 dm3 molβˆ’1 cmβˆ’1

(b) 0.9506%

11A.4 (a) 55 dm3 molβˆ’1 cmβˆ’1

(b) 0.048

11A.5 659.999936 nm

7.02 Γ— 107 m sβˆ’1

11A.6 8.3 Γ— 105 K

11A.7 (a) 53 ps

(b) 5.3 ps

(c) 160 ps

11A.8 (a) 53 cmβˆ’1

(b) 0.27 cmβˆ’1

Topic 11B Rotational spectroscopy

11B.1 3.6 Γ— 1033

11B.2 (a) (i) 4.601 Γ— 10βˆ’48 kg m2

(ii) 9.194 Γ— 10βˆ’48 kg m2

(iii), (iv) 7.150 Γ— 10βˆ’46 kg m2

(b) (i) 1.824 Γ— 1012 Hz

60.84 cmβˆ’1

(ii) 9.126 Γ— 1011 Hz

30.44 cmβˆ’1

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(iii), (iv) 1.174 Γ— 1010 Hz

0.3915 cmβˆ’1

11B.3 (b) 2.66 Γ— 109 sβˆ’1

0.0888 cmβˆ’1

11B.4 𝐼βŠ₯ = 4π‘šBπ‘ŸB2

𝐼βˆ₯ = 2π‘šBπ‘ŸB2

11B.5 𝐴 = 5.149 GHz

𝐡 = 10.30 GHz

11B.6 (a) 289

(b) 17

11B.7 232.1 pm

11B.8 Β½

11B.9 (a) 10

(b) 19

11B.10 474 K

11B.11 (a) (i) (ii) (iii),(iv)

(b) all

11B.13 (a) 636 GHz

(b) 21.2 cmβˆ’1

11B.14 5990749.416 MHz

11B.15 116.2 pm

11B.16 20643 cmβˆ’1

Topic 11C Vibrational spectroscopy

11C.1 (a) 4.49 Γ— 1013 Hz

(b) 4.39 Γ— 1013 Hz

11C.2 (a) 3

(b) 4

(c) 48

(d) 54

11C.3 329 N mβˆ’1

11C.4 (a) (i) HF: 967.4 N mβˆ’1

(ii) HCl: 515.8 N mβˆ’1

(iii) HBr: 411.8 N mβˆ’1

(iv) HI: 314.3 N mβˆ’1

(b) DF: 2930 cmβˆ’1

DCl: 2114 cmβˆ’1

DBr: 1874 cmβˆ’1

DI: 1634 cmβˆ’1

11C.6 3724.66 cmβˆ’1

11C.7 π‘₯e = 0.0062

11C.8 2699.9 cmβˆ’1

Topic 11D Electronic spectroscopy

11D.1 [A] = 0.56 mol dm–3

[B] = 0.16 mol dm

–3

11D.2 1.737 Γ— 10βˆ’15 J

11D.3 50.8 nm

11D.4 1.602 Γ— 10βˆ’15 J

11D.5 (a) 2.04 Γ— 10βˆ’19 J

(b) 669 km sβˆ’1

Topic 11E The decay of excited states

11E.2 0.57

11E.3 4.7 nm

Answers to problems

11.1 33 ΞΌg dmβˆ’3

11.2 (a) 162 pm

(b) 179 GHz

11.3 (b) 3.2645 GHz

(c) 237.6 pm

11.4 οΏ½ΜƒοΏ½ = 0.2029 cmβˆ’1

οΏ½ΜƒοΏ½ = 6.233 Γ— 10βˆ’8 cmβˆ’1

11.5 ROC = 116.28 pm

RCS = 155.97 pm

11.9 (b) 126.5 pm

11.11 π‘˜Q = 5.16 Γ— 106 molβˆ’1 dm3 sβˆ’1

11.12 kF = 1.276 1010

mol–1

dm3 s

–1

11.13 kQ =9.146 109 mol

–1 dm

3 s

–1

𝑑1/2 = 0.172 ΞΌs

11.14 407 ps

11.15 3.49 nm

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Answers to projects

11.1 (a) 4200

(b) 588 nm

11.2 𝐽max = (π‘˜π‘‡/β„Žπ΅)1/2 βˆ’ Β½

11.5 2.6 nm

Focus 12

Statistical thermodynamics

Answers to exercises

Topic 12A The Boltzmann distribution

12A.1 𝑁2

𝑁1= 0.37

12A.2 524 K

12A.3 𝑁5

𝑁0= 7.4

Topic 12B The partition function

12B.1 (a) 𝓆 = 1 + 6eβˆ’2πœ€/π‘˜π‘‡ + 3eβˆ’5πœ€/π‘˜π‘‡

(b) 𝓆 = 1

(c) 𝓆 = 10

12B.2 (a) 𝓆T = 1.45 Γ— 1027

(b) 𝓆T = 6.49 Γ— 1027

12B.3 (a) 𝓆T = 3.2 Γ— 104

(b) 𝓆T = 6.2 Γ— 1027

12B.4 (a) 𝓆R = 19.5

(b) 𝓆R = 265

12B.5 eqn 12B.6: 𝓆V = 1.39

eqn 12B.7: 𝓆V = 0.789

12B.6 𝓆E = 4.23

Topic 12C The origin of thermodynamic

properties

12C.1 οΏ½Μ…οΏ½ = (5eβˆ’πœ€/π‘˜π‘‡+9eβˆ’3πœ€/π‘˜π‘‡

1+5eβˆ’πœ€/π‘˜π‘‡+9eβˆ’3πœ€/π‘˜π‘‡) πœ€

12C.2 (a) 1.25 kJ molβˆ’1

(b) 2.08 kJ molβˆ’1

12C.3 βˆ’37.4 kJ molβˆ’1

Answers to problems

12.1 (a) 𝑁4

𝑁2= 1.753

(b) 𝑁4

𝑁2= 2.27

12.2 (a) 𝓆𝑅 = βˆ‘ 𝑔𝐽𝐽=0 eβˆ’πœ€π½/π‘˜π‘‡: 𝓆𝑅 = 24.816,

Using eqn 12B.5: 𝓆R = 24.474

12.4 11350 K

12.5 (a) 1.401 (at 500 K)

(b) 3.147 (at 1000 K )

12.6 1.28 Γ— 1034

12.7 (a) qE = 5

(c) 6.730

12.8 (a) 𝓆E = 1.293 (at 10 K )

𝓆E = 7.825 (at 298 K )

12.9 𝓆V = 2.14

𝑆m = 14.6 J Kβˆ’1molβˆ’1

𝟏𝟐.10 183.1 J Kβˆ’1molβˆ’1

12.11 (a) Sꝋ(Xe) > S

ꝋ(Ne)

(b) Sꝋ(D2O) > S

ꝋ(H2O)

(c) Sꝋ(graphite) > S

ꝋ(diamond)

12.12 βˆ’54.3 kJ molβˆ’1

12.13 𝐾 = 1.336 Γ— 10βˆ’25

12.14 𝐾 = 1.951 Γ— 10βˆ’11

Focus 13

Magnetic Resonance

Answers to exercises

Topic 13A Nuclear magnetic resonance

13A.1 (a) Tβˆ’1 Hz

(c) A s kgβˆ’1

13A.2 𝐸3/2 = βˆ’1.949 Γ— 10βˆ’26 J

𝐸1/2 = βˆ’6.498 Γ— 10βˆ’27 J

πΈβˆ’1/2 = 6.498 Γ— 10βˆ’27 J

πΈβˆ’3/2 = 1.949 Γ— 10βˆ’26 J

13A.3 2.263

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13A.4 (a) 2.9 Γ— 10βˆ’5

(c) 7.3 Γ— 10βˆ’6

13A.5 300.5 MHz

13A.6 18.79 T

Topic 13B The information in NMR spectra

13B.1 3.17 kHz

13B.2 (a) 9.1 ΞΌT

(b) 38 ΞΌT

13B.3 (a) 11

(b) 5

13B.4 (a) 2.4 kHz

(b) 6.0 kHz

13B.5 octet

13B.6 3.78 ms

Topic 13C Electron paramagnetic resonance

13C.1 4.64 Γ— 10βˆ’24 J

13C.2 (a) 9.02 Γ— 10βˆ’4

(b) 2.7 Γ— 10βˆ’3

13C.3 9.25 GHz, 32.4 mm

13C.4 2.0022

13C.5 π‘Ž = 64.5 MHz

13C.6 (a) 1:3:3:1

(b) 1:3:6:7:6:3:1

13C.7 (a) 331.9 mT

(b) 1.201 T

13C.8 terminal: 0.64

central: 0.180

Answers to problems

13.8 (a) 𝐴′ = 1.9 Hz

𝐡′ = βˆ’1.4 Hz

𝐢′ = 6.4 Hz

(b) 109 Β°

13.9 2600 sβˆ’1

13.10 64 sβˆ’1

13.12 1

13.13 𝟏 0.011 mT: 0.0049

𝟏 0.172 mT: 0.0764

𝟐 0.272 mT: 0.1209

𝟐 0.450 mT: 0.2000

𝟐 0.108 mT: 0.0480

πŸ‘ 0.112 mT: 0.0498

Focus 14

Macromolecules and aggregates

Answers to exercises

Topic 14A Biological and synthetic

macromolecules

14A.1 οΏ½Μ…οΏ½n = 95 kg molβˆ’1

οΏ½Μ…οΏ½w = 93 kg molβˆ’1

14A.2 3.4

14A.3 (a) 0.880 ΞΌm

(b) 31.1 nm

(c) 12.7 nm

14A.4 𝑅c = 2.74 ΞΌm

𝑅rms = 29.1 nm

14A.5 13000

14A.6 βˆ’0.042 J Kβˆ’1molβˆ’1

14A.7 8 aJ

Topic 14B Mesophases and disperse systems

14B.1 5.8 cm

14B.2 23 mN mβˆ’1

14B.3 (a) 1.4 kPa

(b) 0.14 kPa

14B.4 97 mmol mβˆ’2

Answers to problems

14.1 οΏ½Μ…οΏ½n = 20 kg molβˆ’1

οΏ½Μ…οΏ½w = 22 kg molβˆ’1

14.2 οΏ½Μ…οΏ½w/οΏ½Μ…οΏ½n = 1.27

14.4 β„± = 1.37 pN

14.6 pH = 6.9

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14.7 68 ΞΌJ

Answers to projects

14.1 (a) βŸ¨π‘…2⟩1/2 = 10.9 nm

(b) βŸ¨π‘…βŸ© = 10.0 nm

(c) π‘…βˆ— = 8.89 nm

14.3 (a) 2.70 pN

Focus 15

Solids

Answers to exercises

Topic 15A Crystal structure

15A.1 𝑉 = 0.396 nm3

𝜌 = 2.41 Γ— 103kg mβˆ’3

15A.2 𝑁 = 3.9

𝜌 = 4.01 Γ— 103 kg mβˆ’3

πŸπŸ“π€.3 (a) 221 pm

(b) 110 pm

15A.4 {1 1 1} 330 pm, {2 1 1} 234 pm,

{1 0 0} 572 pm

15A.5 {1 2 3} 135 pm

{2 3 6} 70 pm

15A.6 564 pm

15A.7 π‘Ž = 363 pm

𝑐 = 564 pm

15A.8 112 pm

15A.9 1.28 mV

15A.10 66.1 pm

15A.11 π‘Ž = 798 pm

Topic 15B Bonding in solids

15B.1 (a) zinc-blende

(b) zinc blende

(c) rock-salt

15B.2 Ξ”L𝐻ꝋ(SrO)

Ξ”L𝐻ꝋ(CaO)= 0.947

15B.3 3000 kJ molβˆ’1

Topic 15C The properties of solids

15C.3 549 nm

Answers to problems

15.2 (321). (111). (122). (32Μ…2Μ…).

15.6 bcc

15.7 (b) 8.97 Γ— 103 kg mβˆ’3

15.8 0.740

15.9 0.740 g cmβˆ’3

15.10 520 nm

15.11 (a) 424 nm

(b) 600 nm

15.12 (a) less dense

(b) 92 per cent

15.15 𝑉 = βˆ’π‘π‘§2𝑒2Ο€

48πœ€0𝑑

15.16 βˆ’8.16 Γ— 10βˆ’18 J

15.18 +3500 kJ molβˆ’1

15.19 +2421 kJ molβˆ’1


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