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 ร— 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 โˆ’243.6 โ„ƒ 1A.10 394 K 1A.11 (a) 3.6 m 3 (b) 178 m 3 1A.12 3.4 ร— 10 5 m 3 1A.13 benzene 0.355๏ผŒ toluene 0.645 1A.14 (a) 1.32 ร— 10 โˆ’3 m 3 (b) 61.2 ร— 10 3 Pa Topic 1B The kinetic model of gases 1B.1 (a) 493 m s โˆ’1 (b) 615 m s โˆ’1 1B.2 (a) mean (79 K) = 647 m s โˆ’1 mean (315 K) = 1.29 km s โˆ’1 mean (1500 K) = 2.82 km s โˆ’1 (b) mean (79 K) = 323 m s โˆ’1 mean (315 K) = 645 m s โˆ’1 mean (1500 K) = 1.41 km s โˆ’1 1B.3 3.72 1B.4 N 2 0.80 g He 0.30 g 1B.5 65 mPa 1B.6 = 0.97 ฮผm = 120 ร— 10 3 1B.7 (a) 7.0 ร— 10 10 (b) 7.0 ร— 10 8 (c) 7.0 ร— 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 โˆ’3.37 ร— 10 โˆ’5 m 3 mol โˆ’1 1C.5 โˆ’3.49 ร— 10 โˆ’8 Pa โˆ’1 1C.6 (a) (i) 101 kPa (ii) 83.1 MPa (b) (i) 101 kPa (ii) 206 MPa 1C.7 โˆ’0.608 MPa 1C.8 = 4.6 ร— 10 โˆ’5 m 3 mol โˆ’1 = 0.66 1C.9 1842 K Answers to problems 1.1 0.50 m 3 1.2 28.82 g mol โˆ’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 โˆ’1 1.7 16.4 g mol โˆ’1

Transcript of The properties of gases

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 ร— 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 โˆ’243.6 โ„ƒ

1A.10 394 K

1A.11 (a) 3.6 m3

(b) 178 m3

1A.12 3.4 ร— 105 m3

1A.13 benzene 0.355๏ผŒ toluene 0.645

1A.14 (a) 1.32 ร— 10โˆ’3m3

(b) 61.2 ร— 103 Pa

Topic 1B The kinetic model of gases

1B.1 (a) 493 m sโˆ’1

(b) 615 m sโˆ’1

1B.2 (a) ๐‘ฃmean(79 K) = 647 m sโˆ’1

๐‘ฃmean(315 K) = 1.29 km sโˆ’1

๐‘ฃmean(1500 K) = 2.82 km sโˆ’1

(b) ๐‘ฃmean(79 K) = 323 m sโˆ’1

๐‘ฃmean(315 K) = 645 m sโˆ’1

๐‘ฃmean(1500 K) = 1.41 km sโˆ’1

1B.3 3.72

1B.4 ๐‘šN2 0.80 g

๐‘šHe 0.30 g

1B.5 65 mPa

1B.6 ๐œ† = 0.97 ฮผm

๐‘ = 120 ร— 103

1B.7 (a) 7.0 ร— 1010

(b) 7.0 ร— 108

(c) 7.0 ร— 104

1B.9 (a) 6.8 nm

(b) 68 nm

(c) 6.8 mm

Topic 1C Real gases

1C.1 ๐‘c = 0.242

1C.2 CH4 ๐‘c = 0.288

C2H6 ๐‘c = 0.274

C3H8 ๐‘c = 0.276

1C.3 2.15 MPa

1C.4 โˆ’3.37 ร— 10โˆ’5 m3molโˆ’1

1C.5 โˆ’3.49 ร— 10โˆ’8 Paโˆ’1

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

(ii) 83.1 MPa

(b) (i) 101 kPa

(ii) 206 MPa

1C.7 โˆ’0.608 MPa

1C.8 ๐‘ = 4.6 ร— 10โˆ’5 m3 molโˆ’1

๐‘ = 0.66

1C.9 1842 K

Answers to problems

1.1 0.50 m3

1.2 28.82 g molโˆ’1

130 kg

1.3 6.8 kPa

1.4 713 Torr

1.5 ๐‘ฅN2= 0.7809

๐‘ฅO2= 0.2094

๐‘ฅAr = 0.0098

1.6 132 g molโˆ’1

1.7 16.4 g molโˆ’1

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

ANSWERS TO END OF CHAPTER EXERCISES

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1.8 (a) ๐‘H2= 200 kPa

๐‘N2= 100 kPa

(b) 300 kPa

1.9 (a) 72 K

(b) 943 m sโˆ’1

1.10 1.0 ร— 1013 sโˆ’1

1.11 0.57 dm3 molโˆ’1

1.12 ๐‘Ž = 0.656 Pa m6molโˆ’2

๐‘ = 5.54 ร— 10โˆ’5 m3 molโˆ’1

1.13 ๐‘Ž = 0.321 Pa m6 molโˆ’2

๐‘ = 6.50 ร— 10โˆ’5 m3molโˆ’1

๐‘Ÿ = 1.86 ร— 10โˆ’10 m

1.14 ๐‘Ž = ๐ŸŽ. ๐Ÿ๐Ÿ๐Ÿ– ๐๐š ๐ฆ๐Ÿ” ๐ฆ๐จ๐ฅโˆ’๐Ÿ

๐‘ = ๐Ÿ‘. ๐Ÿ“ ร— ๐Ÿ๐ŸŽโˆ’๐Ÿ“๐ฆ๐Ÿ‘ ๐ฆ๐จ๐ฅโˆ’๐Ÿ

Answers to projects

1.1 (d) ๐‘“ โ‰ˆ 10โˆ’2

1.2 (a) 720 Mbar

(d) 0.21 Mbar

(e) 0.029 Mbar

1.3 (c) 1030 K

1.4 (c) ๐‘c = 101.3 bar

๐‘‰c = 0.1327 dm3 molโˆ’1

๐‘‡c = 431.3 K

Focus 2

The First Law of thermodynamics

Answers to exercises

Topic 2A Work

2A.1 (a) ๐‘คexpansion = โˆ’0.10 J

(b) ๐‘คexpansion = โˆ’100 J

(a) ๐‘คcompression = +0.10 J

(b) ๐‘คcompression = +100 J

2A.2 โˆ’5.5 kJ

2A.3 (a) โˆ’99 J

(b) โˆ’167 J

2A.4 +123 J

2A.5 +29.9 J

2A.6 โˆ’1.25 kJ

2A.7 (a) 0

(b) โˆ’783 J

2A.8 โˆ’100 J

Topic 2B Heat

2B.1 23.7 J Kโˆ’1

2B.2 (a) 27 J Kโˆ’1

(b) 0.45 J Kโˆ’1gโˆ’1

(c) 25 J Kโˆ’1molโˆ’1

2B.3 42 kJ

2B.4 87 kJ

2B.5 ๐ถ๐‘‰,m = 29.9 J Kโˆ’1molโˆ’1

๐ถ๐‘,m = 38.2 J Kโˆ’1molโˆ’1

Topic 2C Internal energy

2C.1 โˆ’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 ฮ”๐ป = ๐‘ž๐‘ = โˆ’1.2 kJ

๐ถ๐‘ = 80 J Kโˆ’1

2D.5 ฮ”๐ป = ๐‘ž๐‘ = +2.2 kJ

ฮ”๐‘ˆ = +1.6 kJ

2D.6 28.25 J Kโˆ’1molโˆ’1

Topic 2E Physical change

2E.1 1740 kJ molโˆ’1

2E.2 19.5 kJ molโˆ’1

2E.3 +492 kJ molโˆ’1

2E.4 +2.83 ร— 104 kJ

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

ANSWERS TO END OF CHAPTER EXERCISES

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2E.5 (a) +2.44 kJ molโˆ’1

(b) +2.26 kJ molโˆ’1

2E.6 +93 kJ molโˆ’1

2E.7 ๐‘ž๐‘ = ฮ”๐ป = +80.0 kJ

๐‘ค = โˆ’5.20 kJ

ฮ”๐‘ˆ = +74.8 kJ

2E.8 2.58 kJ molโˆ’1

2E.9 +239 kJ molโˆ’1

Topic 2F Chemical change

2F.1 โˆ’124 kJ molโˆ’1

2F.2 (a) 388 kJ molโˆ’1

(b) smaller

(c) ฮ”f๐ปo โˆ’ 38 kJ molโˆ’1

2F.3 398 kJ molโˆ’1

2F.4 (a) +16 kJ molโˆ’1

(b) โˆ’772 kJ molโˆ’1

2F.5 (a) โˆ’1560 kJ molโˆ’1

(b) +51.88 kJ gโˆ’1

(c) methane: +55.5 kJ gโˆ’1

ethane is less exothermic

2F.6 โˆ’4564.7 kJ molโˆ’1

2F.7 โˆ’85 kJ molโˆ’1

2F.8 (a) โˆ’3290 kJ

(b) โˆ’2710 kJ

2F.9 โˆ’432 kJ molโˆ’1

2F.10 +225 kJ molโˆ’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 molโˆ’1

(b) 274 kJ molโˆ’1

(c) 150 kJ molโˆ’1

(d) 449 kJ molโˆ’1

2.6 +2.468 kJ molโˆ’1

2.7 (a) 20.83 J Kโˆ’1molโˆ’1

(b) (i) +641 J molโˆ’1

(ii) +458 J molโˆ’1

2.8 +39.8 kJ molโˆ’1

2.9 2.38 kJ molโˆ’1

2.10 +40.88 kJ molโˆ’1

2.11 +1152 kJ

2.12 4.22 kJ Kโˆ’1

+0.768 K

2.13 (a) โˆ’2800 kJ molโˆ’1

(b) โˆ’2800 kJ molโˆ’1

(c) โˆ’1.27 ร— 103 kJ molโˆ’1

2.14 (a) โˆ’1333 kJ molโˆ’1

(b) โˆ’1331 kJ molโˆ’1

(c) โˆ’815 kJ molโˆ’1

2.15 +112.27 kJ molโˆ’1

2.16 โˆ’382.96 kJ molโˆ’1

2.17 (a) โˆ’57.29 kJ molโˆ’1

(b) โˆ’28.6 kJ molโˆ’1

(c) โˆ’138.2 kJ molโˆ’1

(d) โˆ’32.88 kJ molโˆ’1

(e) โˆ’55.84 kJ molโˆ’1

2.19 (a) +1.9 kJ molโˆ’1

(b) +30.6 kJ molโˆ’1

2.20 (a) โˆ’2205 kJ molโˆ’1

(b) โˆ’2200 kJ molโˆ’1

2.21 +11.3 kJ molโˆ’1

2.22 โˆ’56.98 kJ molโˆ’1

2.23 (a) decrease

(b) increase

(c) decrease

2.24 (a) increase

(b) increase

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

ANSWERS TO END OF CHAPTER EXERCISES

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2.25 +7.04 J molโˆ’1

Answers to projects

2.1 (a) more negative

(b) more positive

2.2 (a) ๐‘ค = โˆ’๐‘›๐‘…(๐‘‡i + ๐‘๐‘‰i) ln(๐‘‰f/๐‘‰i) + ๐‘›๐‘…๐‘(๐‘‰f โˆ’ ๐‘‰i)

(b) w more negative

2.3 (a) ฮ”๐‘ˆm = ยผ๐‘Ž๐‘‡4

(b) ๐ถ๐‘‰,m = ๐‘ + 2๐‘๐‘‡

2.4 (a) +818 J molโˆ’1

2.6 (a) 40000 K

2.7 ๐‘Ž = 29.74 J Kโˆ’1molโˆ’1

๐‘ = 2.51 ร— 10โˆ’2 J Kโˆ’2molโˆ’1

๐‘ = โˆ’1.55 ร— 105 J K molโˆ’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 Kโˆ’1

(b) +1.2 J Kโˆ’1

3A.2 +0.41 J Kโˆ’1

3A.3 1470 K

Topic 3B Entropy changes

3B.1 +14 J Kโˆ’1molโˆ’1

3B.2 2.89 dm3

3B.3 +23.6 J Kโˆ’1

3B.4 โˆ’93.0 J Kโˆ’1

3B.5 โˆ’45.1 kJ

โˆ’165 J Kโˆ’1

3B.6 (a) +120 J Kโˆ’1

(b) โˆ’120 J Kโˆ’1

3B.7 +0.95 J Kโˆ’1molโˆ’1

3B.8 (a) +122 J Kโˆ’1

(b) +130 J Kโˆ’1

(c) +606 J Kโˆ’1

The total entropy change of the system:

+858 J Kโˆ’1

3B.9 (a) +85 J Kโˆ’1molโˆ’1

(b) +34 kJ molโˆ’1

3B.10 (a) +87.8 J Kโˆ’1molโˆ’1

(b) โˆ’87.8 J Kโˆ’1molโˆ’1

Topic 3C Absolute entropy

3C.1 6.69 mJ Kโˆ’1molโˆ’1

3C.3 +11.5 J Kโˆ’1molโˆ’1

Topic 3D The Gibbs energy

3D.1 (a) positive

(b) negative

(c) positive

3D.2 (a) โˆ’412.9 J Kโˆ’1molโˆ’1

(b) +92.6 J Kโˆ’1molโˆ’1

(c) โˆ’153.1 J Kโˆ’1molโˆ’1

(d) โˆ’21.0 J Kโˆ’1molโˆ’1

(e) +512.0 J Kโˆ’1molโˆ’1

3D.3 (a) โˆ’198.72 J Kโˆ’1 molโ€“1

(b) +309 J Kโˆ’1 molโˆ’1

Answers to problems

3.1 (a) +33 J Kโˆ’1

3.2 โˆ’7.9 J Kโˆ’1molโˆ’1

3.3 0.63 ๐‘‡i

3.5 +5.1 J Kโˆ’1

3.6 +79 J Kโˆ’1molโˆ’1

3.7 (b) 4.1 ร— 10โˆ’23 J Kโˆ’1

3.8 (c) 3.37 J Kโˆ’1 molโˆ’1

3.9 4.0 ร— 10โˆ’4J Kโˆ’1molโˆ’1

Page 5: The properties of gases

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

ANSWERS TO END OF CHAPTER EXERCISES

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3.10 0.256 J Kโˆ’1molโˆ’1

3.11 +5.03 kJ Kโˆ’1

3.12 (a) โˆ’0.69 J Kโˆ’1molโˆ’1

(b) +0.14 J Kโˆ’1molโˆ’1

3.13 (a) โˆ’93 kJ molโˆ’1

(b) Yes

(c) +300 J Kโˆ’1molโˆ’1

3.14 0.41 g

3.15 +17 J

3.16 8.2 ร— 1023molecules

Answers to projects

3.1 (a) 3.3 kW

(b) 180 kW

3.2 ฮ”๐‘† = ๐‘Ž ln(๐‘‡f/๐‘‡i) + ๐‘(๐‘‡f โˆ’ ๐‘‡i)

โˆ’ยฝ๐‘(๐‘‡fโˆ’2 โˆ’ ๐‘‡i

โˆ’2)

3.3 (b) 2.02 ร— 10โˆ’22 J Kโˆ’1molโˆ’1

(d) ๐‘„

๐‘< 0.01

3.4 (a) Yes

(b) 0.46 mol

(c) โˆ’12 W mโˆ’3

(d) battery: โˆ’150 ร— 103 W mโˆ’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 molโˆ’1

(b) โˆ’20 kJ molโˆ’1

4A.5 +4.2 kJ molโˆ’1

4A.6 โˆ’3.5 kJ molโˆ’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 molโˆ’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 molโˆ’1

4C.4 +32.631 J molโˆ’1

4C.5 (a) โˆ’1.31 kJ molโˆ’1

(b) +4.38 J Kโˆ’1molโˆ’1

(c) spontaneous

4C.6 (a) ฮ”๐บm โˆ’ 1.40 kJ molโˆ’1

ฮ”๐‘†m + 4.71 J Kโˆ’1molโˆ’1

(b) spontaneous

4C.7 4.99 kPa

Topic 4D Solutions

4D.1 17.5 g

4D.2 8.92 ร— 10โˆ’2 mol kgโˆ’1

4D.3 ๐‘sucrose = 0.403 mol dmโˆ’3

๐‘sucrose = 0.388 mol kgโˆ’1

4D.4 1.80 ร— 10โˆ’3

4D.5 โˆ’37 J molโˆ’1

4D.6 ๐‘ฅCO2= 4.8 ร— 10โˆ’3

4D.7 129 kPa

4D.8 7985 Pa

4D.9 (a) 1.3 mmol dmโˆ’3

(b) 17.0 mmol dmโˆ’3

4D.10 ๐‘N2= 0.51 mmol kgโˆ’1

๐‘O2= 0.28 mmol kgโˆ’1

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

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4D.11 34.3 mmol dmโˆ’3

4D.12 ๐‘ฅT = 0.93 ๐‘ฅX ๏ผ0.07

๐‘ฆT = 0.97 ๐‘ฆX = 0.03

4D.13 +5.6 kJ molโˆ’1

Topic 4E Colligative properties

4E.1 59.1 g molโˆ’1

4E.2 +0.061 K

4E.3 +0.36 K

4E.4 207 g molโˆ’1

Topic 4F Phase diagrams of mixtures

4F.1 ๐‘›โ€ฒ

๐‘›โ€ฒโ€ฒ = 0.31

4F.2 ๐‘Eโ€ฒ (aq) = 0.050 mol dmโˆ’3

๐‘Eโ€ฒ (org) = 0.0075 mol dmโˆ’3

4F.3 0.25

Answers to problems

4.1 (b) 711 K

4.3 (a) โˆ’0.1346 bar Kโˆ’1

(b) +135.6 bar

4.4 (a) 31.69 kJ molโˆ’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) ๐‘ฆeth = 0.96111

๐‘ฆchl = 0.03889

(d) 692 Torr

4.13 (a) 43.95 Torr

(b) 1.13 Torr

(c) 22.6 kPa

4.14 6.41 ร— 103 kPa

4.15 A: ๐พHโ€ฒ = 861 Torr

B: ๐พHโ€ฒ = 1103 Torr

4.16 A: KH = 242 Torr

B: KH = 397 Torr

4.17 0.11 C

4.18 ๐‘€ = 88.19 kg molโˆ’1

4.19 13.9 kg molโˆ’1

4.20 (a) yT = 0.36

(b) yT = 0.81

4.21 (a) 0.150

(b) ๐‘›โ€ฒ

๐‘›โ€ฒโ€ฒ = 9.81

4.22 (a) 0.345

(b) ๐‘›โ€ฒ

๐‘›โ€ฒโ€ฒ = 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) ๐‘ฅethanol = 0.072

(b) 53.1039 cm3 mol

-1

4.4 (a) ๐‘‰water/cm3 molโˆ’1 =

18.068 + 6.557 ร— 10โˆ’3๐‘2 โˆ’ 1.018 ร— 10โˆ’3๐‘3

4.5 (a) 4.4 cm3O2

(b) 4.0 atm: 56 ฮผg N2,

1.0 atm: 14 ฮผg N2

(c) 170 ฮผg N2

Focus 5

Chemical change

Answers to exercises

Topic 5A The thermodynamics of reaction

5A.1 (a) ๐‘„ = ๐‘CO2(g)

6

[CH3COCOOH]2๐‘O2(g)5 ร— (๐‘o2/๐‘o)

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(b) ๐‘„ = [FeSO4]

[PbSO4]

(c) ๐‘„ = [HCl]2

๐‘H2(g)ร—

๐‘o

๐‘o2

(d) ๐‘„ = [CuCl2]

[CuCl]2 ร— ๐‘o

5A.2 +12.3 kJ molโˆ’1

5A.3 +6.8 kJ molโˆ’1

5A.4 โˆ’25.1 kJ molโˆ’1

5A.5 +26 kJ molโˆ’1

5A.7 โˆ’14.4 kJ molโˆ’1

formation of NH3

5A.8 2.31

5A.9 (a) 5.2 ร— 1011

(b) 850

5A.10 1

5A.11 โˆ’2.42 kJ molโˆ’1

5A.12 3.01

5A.13 glucose-1-phosphate 3.4 ร— 103

glucose-6-phosphate 2.5 ร— 102

glucose-3-phosphate 36

Topic 5B The equilibrium constant

5B.1 ๐‘CO2= 10.2 kPa

5B.2 3.3 ร— 106

5B.3 6.94

5B.4 3.1 ร— 10โˆ’3

5B.5 4.31 ร— 1043

Topic 5C Response to conditions

5C.1 (a) 52.9 kJ molโˆ’1

(b) โˆ’52.9 kJ molโˆ’1

5C.2 โˆ’92.2 kJ molโˆ’1

5C.3 ๐พ = 7.23 ร— 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 dmโˆ’3

pH = 2.0

(b) 5.01 ร— 10โˆ’13mol dmโˆ’3

pH = 12.3

(c) 53 mmol dmโˆ’3

pH = 1.3

Topic 5E Polyprotic acids

5E.1 (a) 9.7 ร— 10โˆ’4

(b) 3.8 ร— 10โˆ’10

5E.2 (a) ๐‘“(H2S) = 1.0

๐‘“(HSโˆ’) = 1.3 ร— 10โˆ’3

๐‘“(S2โˆ’) = 9.2 ร— 10โˆ’14

undissociated (H2S) form

(b) ๐‘“(H2S) = 7.7 ร— 10โˆ’4

๐‘“(HSโˆ’) = 1.0

๐‘“(S2โˆ’) = 7.1 ร— 10โˆ’5

HSโ€“ ions

Topic 5F Acidโ€“base equilibria of salts in water

5F.1 4.36

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5F.2 (a) acidic

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

(b) basic

H2O(l) + CO32โ€“(aq) โ‡Œ HCO3

(aq) + OHโ€“(aq)

(c) basic

H2O(l) + Fโ€“ (aq) โ‡Œ HF(aq) + OHโ€“(aq)

(d) neutral

(e) acidic

[Al(H2O)6]3+(aq) + H2O(l) โ‡Œ

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

(f) acidic

[Co(H2O)6]2+(aq) + H2O(l) โ‡Œ

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

5F.3 (a) pH 2โ€“4

(b) pH 3โ€“5

(c) pH 11.5โ€“13.5

(d) pH 6โ€“8

(e) pH 5โ€“7

5F.4 (a) H3PO4 and NaH2PO4

(b) NaH2PO4 and Na2HPO4, or

NaHSO3 and Na2SO3

Topic 5G Solubility equilibria

5G.2 (a) 1.0 ร— 10โˆ’5 mol dmโˆ’3

(b) 1.2 ร— 10โˆ’4 mol dmโˆ’3

(c) 9.3 ร— 10โˆ’11 mol dmโˆ’3

(d) 6.9 ร— 10โˆ’7 mol dmโˆ’3

5G.3 (a) 5.5 ร— 10โˆ’10mol dmโˆ’3

(b) 3.2 ร— 10โˆ’3 mol dmโˆ’3

(c) 1.6 ร— 10โˆ’7 mol dmโˆ’3

(d) 2.5 ร— 10โˆ’7 mol dmโˆ’3

Topic 5H Ions in solution

5H.1 1.35

5H.3 7.63 mS m2molโˆ’1

5H.4 347 ฮผm sโˆ’1

Topic 5I Electrochemical cells

5I.2 (a) ๐‘ฃ = 2

(b) ๐‘ฃ = 2

(c) ๐‘ฃ = 4

(d) ๐‘ฃ = 2

(e) ๐‘ฃ = 2

(f) ๐‘ฃ = 1

5I.3 โˆ’212 kJ molโˆ’1

5I.4 +7.7 kJ molโˆ’1

Topic 5J Standard potentials

5J.1 Exercise 5I.1

(a) 0

(b) 0

(c) +0.87 V

(d) โˆ’0.27 V

(e) โˆ’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 ๐ธโŠ• = +1.14 V

ฮ”r๐บโŠ• = โˆ’440 kJ molโˆ’1

5J.3 110

5J.4 0.320 V

Answers to problems

5.1 (a) โˆ’91.14 kJ molโˆ’1

(b) +594.6 kJ molโˆ’1

(c) โˆ’66.8 kJ molโˆ’1

(d) +99.8 kJ molโˆ’1

(e) โˆ’415.80 kJ molโˆ’1

5.2 +279 kJ molโˆ’1

5.3 (a) โˆ’32 kJ molโˆ’1

(b) (i) โˆ’49 kJ molโˆ’1

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(ii) โˆ’67 kJ molโˆ’1

5.4 โˆ’0.7 kJ molโˆ’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 ๐พr1/๐พr2 = 1.4 ร— 1046

5.11 โˆ’245 kJ molโˆ’1

5.12 0.0958, 0.9042

5.13 ๐‘NH3(g) = 1.93 bar

๐‘H3(g) = 1.10 bar

๐‘N3(g) = 0.03 bar

5.14 2.7 ร— 10โˆ’4bar

5.15 (a) โŒˆPCl5โŒ‰ = 0.016 mol dmโˆ’3

[PCl3] = [Cl2] = 0.013 mol dmโˆ’3

(b) 45 per cent

5.16 ๐‘H2(g) โ‰ˆ 0.20 bar

๐‘N2(g) โ‰ˆ 0.20 bar

๐‘NH3(g) = 7.6 ร— 10โˆ’5 bar

5.17 +41.1 kJ molโˆ’1

5.19 (a) 9.24

(b) โˆ’12.9 kJ molโˆ’1

(c) +161 kJ molโˆ’1

(d) +248 J Kโˆ’1molโˆ’1

5.20 โˆ’187.78 kJ molโˆ’1

5.21 (a) +12.50 kJ molโˆ’1

(b) +9.05 kJ molโˆ’1

(c) โˆ’8.6 J Kโˆ’1molโˆ’1

5.22 (a) [H3O+] = 1.6 ร— 10โˆ’7 mol dmโˆ’3

pH = 6.8

(b) [OHโˆ’] = 1.6 ร— 10โˆ’7 mol dmโˆ’3

pOH = 6.8

5.23 (a) 2 D2O(l) โ‡Œ D3O+(aq) + OD

โ€“(aq)

(b) 14.9

(c) 3.67 ร— 10โˆ’8 mol dmโˆ’3

(d) 7.43

(e) pD + pOD = p๐พw = 14.9

5.24 ideal: pH = 0.30

๐›พH3O+ = 0.769: pH = 0.42

5.26 +57.2 kJ molโˆ’1

๐Ÿ“.28 p๐พa = 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 dmโˆ’3

[HOOCCO2โˆ’] = 0.07 mol dmโˆ’3

[(CO2)22โˆ’] = 6.5 ร— 10โˆ’5 mol dmโˆ’3

[H3O+] = 0.07 mol dmโˆ’3

[OHโˆ’] = 1.4 ร— 10โˆ’13 mol dmโˆ’3

5.33 [H2S] = 0.065 mol dmโˆ’3

[HSโˆ’] = 9.2 ร— 10โˆ’5mol dmโˆ’3

[S2โˆ’] = 7.1 ร— 10โˆ’15mol dmโˆ’3

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[H3O+] = 9.2 ร— 10โˆ’5mol dmโˆ’3

[OHโˆ’] = 1.1 ร— 10โˆ’10 mol dmโˆ’3

๐Ÿ“.35 pH = 9.2

5.36 pH = 4.8

5.38 (a) [acid]

[base]= 1.6 ร— 10โˆ’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 ๐พa = 6.92 ร— 10โˆ’6

pKa = 5.16

pH = 3.38

5.44 8.00

5.46 (a) pKa = 3.08

๐พa = 8.32 ร— 10โˆ’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 ฮ”s๐บo = +241 kJ molโˆ’1

5.50 ๐‘  = 1.25 ร— 10โˆ’5 mol dmโˆ’3

5.51 (b) increase

5.52 (a) 2.73 g

(b) 2.92 g

5.53 0.015 mol kgโˆ’1 MgF2

๐›พยฑ,MgF2= 0.538

๐‘ŽMg2+ = 0.0081

๐‘ŽFโˆ’ = 0.016

0.025 mol kgโˆ’1 NaCl

๐›พยฑ,NaCl = 0.733

๐‘ŽNa+ = 0.018

๐‘ŽClโˆ’ = 0.018

5.54 ๐ต = 2.022

5.55 13.83 mS m2molโˆ’1

5.56 (a) 12.6 mS m2 molโˆ’1

(b) 210 S mol1/2m1/2

5.57 1.364 ร— 10โˆ’5 mol dmโˆ’3

5.58 3.70

5.59 4.85

5.60 +28 mV

5.61 โˆ’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) โˆ’1.20 V

(b) โˆ’ 1.19 V

5.65 (a) โˆ’394 kJ molโˆ’1

(b) โˆ’787 kJ molโˆ’1

(c) +75 kJ molโˆ’1

(d) โˆ’284 kJ molโˆ’1

(e) โˆ’291 kJ molโˆ’1

(f) +498 kJ molโˆ’1

5.66 (a) ๐ธcello = โˆ’0.46 V

ฮ”r๐บo = +88.8 kJ molโˆ’1

ฮ”r๐ปo = +146.39 kJ molโˆ’1

(b) +86.9 kJ molโˆ’1

5.67 (a) ๐ธcello = +1.57 V

ฮ”r๐บo = โˆ’606 kJ molโˆ’1

(b) โˆ’604 kJ molโˆ’1

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5.70 (a) โˆ’40 kJ molโˆ’1

(b) +29.7 kJ molโˆ’1

(c) โˆ’313 kJ molโˆ’1

5.71 (a) +0.324 V

(b) +0.45 V

5.72 +0.56 V

5.73 (a) 6.4 ร— 109

(b) 1.3 ร— 107

(c) 9.4 ร— 1043

(d) 1.1 ร— 1025

(e) 8.2 ร— 10โˆ’7

(f) 3.4 ร— 1013

5.75 (a) +0.94 V

(b) {1.51 + 0.041 ร— ln(10โˆ’pH)} V

5.76 +0.22 V

5.77 (a) โˆ’0.6119 V

(b) โˆ’0.22 V

(d) +0.41 V

(e) p๐พa = 10.28

5.79 ฮ”r๐‘†o = โˆ’324 J Kโˆ’1molโˆ’1

ฮ”r๐ปo = โˆ’571 kJ molโˆ’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 dmโˆ’3

6A.2 A: 1.6 mol dmโˆ’3sโˆ’1

B: 0.80 mol dmโˆ’3sโˆ’1

D: 2.4 mol dmโˆ’3sโˆ’1

6A.3 0.80 mol dmโˆ’3sโˆ’1

Topic 6B Rate laws

6B.1 molโˆ’2dm6 sโˆ’1

6B.2 ๐‘˜r1: molโˆ’1dm3sโˆ’1

๐‘˜r2: molโˆ’1dm3

6B.3 ๐‘˜r1: kPaโˆ’1/2sโˆ’1

๐‘˜r2: dimensionless

6B.4 3.7 ร— 106 dm3molโ€“1sโ€“1

Topic 6C Integrated rate laws

6C.1 1.58 ร— 10โˆ’3 sโˆ’1

6C.2 1.12 ร— 10โˆ’4sโˆ’1

6C.5 (a) 14 Pa sโˆ’1

(b) 1.5 ร— 103s

6C.7 1326 s

6C.8 3100 a

6C.9 (a) 0.63 ฮผg

(b) 0.16 ฮผg

6C.10 (a) 0.138 mol dmโˆ’3

(b) 0.095 mol dmโˆ’3

6C.11 13.6 s

6C.12 ๐‘ก1/2 = 5.70 h

(a) 78.4 kPa

(b) 77.6 kPa

Topic 6D The temperature dependence of

reaction rates

6D.1 7.5 ร— 10โˆ’14molโˆ’1dm3sโˆ’1

6D.2 (a) 1.86 ร— 1023a

(b) 75.8 s

6D.3 ๐ด = 1.37 ร— 1015dm3molโˆ’1sโˆ’1

6D.4 298.86 K

6D.5 52 kJ mol1

6D.6 35.9 kJ molโˆ’1

6D.7 121 kJ molโˆ’1

6D.8 โˆ’21.6 kJ molโˆ’1

6D.9 (a) 27.2 kJ molโˆ’1

(b) 54.3 kJ molโˆ’1

6D.10 ๐ด = 1.44 ร— 1012 molโˆ’1 dm3 sโˆ’1

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6D.11 0.8 nm2

Topic 6E The approach to equilibrium

6E.1 7.5 ร— 105 sโˆ’1

6E.2 23.8 msโˆ’1

6E.3 21 ms

Topic 6F Reaction mechanisms

6F.1 39.1 d

6F.2 increase

6F.3 1.89 ร— 10โˆ’6 Paโˆ’1sโˆ’1

Topic 6G Reactions in solution

6G.1 (a) 6.61 ร— 106 m3molโˆ’1sโˆ’1

(b) 3.0 ร— 107 m3molโˆ’1sโˆ’1

6G.2 (a) โˆ’3.1 ร— 1016 mol mโˆ’2sโˆ’1

(b) 1.6 ร— 10โˆ’11mol

6G.3 (a) 27 h

(b) 2.7 ร— 103 h

(c) 3.0 ร— 103 a

6G.4 ๐‘ = 1 ร— 106

6G.5 17 kJ molโˆ’1

Topic 6H Homogeneous catalysis

6H.1 5.6 ร— 1022

6H.2 1.62 mmol dmโˆ’3

6H.3 ๐‘˜cat = 1.18 ร— 105 sโˆ’1

๐œ‚ = 7.9 ร— 106 molโˆ’1dm3sโˆ’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) ๐‘ฃ = ๐‘˜๐‘Ÿ[ICl][H2]

(b) kr = 0.162 mol1

dm3 s1

(c) 20.6 ร— 10โˆ’7mol dmโˆ’3sโˆ’1

6.4 0.248 s1

6.5

(a) second order

(b) 7.80 ร— 10โˆ’3

dm3 mol

โˆ’1 s

โˆ’1

6.6 (a) second order

(b) 1.32 dm3 mol

โ€“1 s

โ€“1

6.9 second order

0.287 molโˆ’1dm3minโˆ’1

6.10 ๐ธa = 272 kJ molโˆ’1

6.11 ๐ธa = 180 kJ molโˆ’1

A = 2.11 molโ€“1

dm3 s

โ€“1

6.12

(a) ๐‘“(20 โ„ƒ) = 1.7 ร— 10โˆ’20

(b) ๐‘“(200 โ„ƒ) = 5.6 ร— 10โˆ’13

๐ด = 3 ร— 1011 molโˆ’1dm3sโˆ’1

6.13 (a) 126 kJ molโˆ’1

(b) ฮ”๐‘†โ€ก = 0

6.15 ๐‘˜r,eff = 7.12 ร— 105 sโˆ’1

๐‘˜rโ€ฒ = 4.00 ร— 1010 molโˆ’1 dm3sโˆ’1

6.16 {๐‘˜b(๐‘˜a/๐‘˜aโ€ฒ )1/2}[A2]1/2[B]

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

(b) first step

6.26 ๐พM = 1.11 ฮผmol dmโˆ’3

๐‘ฃmax = 2.31 ฮผmol dmโ€“3 sโˆ’1

๐‘˜cat = 1.2 ร— 102 sโˆ’1

6.27 ๐พM = 87 mmol dmโˆ’3

๐‘ฃmax = 16 ฮผmol dmโ€“3 sโˆ’1

6.28 ๐›ผ = 2.809 Paโˆ’1

๐‘‰โˆž = 0.5659 cm3

6.29 gold: zeroth order

Platinum: first order

6.33 ๐‘ = 165

๐‘‰mon = 13.1 cm3

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Answers to projects

6.1 (a) 1

[A]0โˆ’[B]0ln (

[B]/[B]0

[A]/[A]0) = ๐‘˜r๐‘ก

(b) 1

[A]โˆ’

1

[A]0= ๐‘˜r๐‘ก

6.2 (b) ๐ธa = 105.1 kJ molโˆ’1

ฮ”r๐บo = โˆ’26.6 kJ molโˆ’1

ฮ”r๐ปo = โˆ’34.3 kJ molโˆ’1

6.6 (a) ๐พM = 24.9 mmol dmโˆ’3

๐‘ฃmax = 4.80 mol dmโˆ’3sโˆ’1

(b) ๐พM = 25.0 mmol dmโˆ’3

๐‘ฃmax = 4.81 mol dmโˆ’3sโˆ’1

(c) ๐พM = 25.0 mmol dmโˆ’3

๐‘ฃmax = 4.80 molโˆ’1 dm3sโˆ’1

Focus 7

Quantum theory

Answers to exercises

Topic 7A The emergence of quantum theory

7A.1 3.05 ร— 10โˆ’19 J

7A.2 8.226 ร— 104 cmโˆ’1

7A.3 (a) 6.6 ร— 10โˆ’19 J

4.0 ร— 102 kJ molโˆ’1

(b) 3.3 ร— 10โˆ’20 J

20 kJ molโˆ’1

(c) 1.3 ร— 10โˆ’33 J

7.8 ร— 10โˆ’13 kJ molโˆ’1

7A.4 (a) ๐ธ(750 nm) = 2.65 ร— 10โˆ’19 J

(b) ๐œˆ(250 nm) = 9.96 ร— 105 m sโˆ’1

7A.5 (a) 6.6 ร— 10โˆ’31m

(b) 6.6 ร— 10โˆ’39 m

(c) 99.7 pm

7A.6 1.3 ร— 106 m sโˆ’1

7A.7 4 ร— 10โˆ’36m

7A.8 (a) 1.10 ร— 10โˆ’27 kg m sโˆ’1

(b) 9.5 ร— 10โˆ’24 kg m sโˆ’1

(c) 3.31 ร— 10โˆ’36 kg m sโˆ’1

7A.9 2.2 ร— 10โˆ’24 m sโˆ’1

Topic 7B The dynamics of microscopic systems

7B.1 ฮ”๐‘ฅ โ‰ฅ 0.900 nm

7B.2 ฮ”๐‘ฃ โ‰ฅ 2.1 ร— 10โˆ’29 m sโˆ’1

7B.3 ฮ”๐‘ฅ โ‰ฅ 1.1 ร— 10โˆ’26 m

7B.4 ฮ”๐‘ฅ = 100 ร— 10โˆ’12 m

ฮ”๐‘ฃ โ‰ฅ 5.8 ร— 105 m sโˆ’1

Topic 7C Translation

7C.1 (a) ๐‘ฅ = ๐ฟ/2

(b) ๐‘ฅ = 3๐ฟ/4

(c) ๐‘ฅ = 5๐ฟ/6

7C.2 9.84 ร— 10โˆ’23 J

7C.3 ๐ฟ = 1.00 ร— 10โˆ’9 m

Topic 7D Rotation

7D.1 ๐‘› = 0: โˆž

๐‘› = 1: 628 pm

๐‘› = 2: 314 pm

7D.2 (a) 4.34 ร— 10โˆ’47 kg m2

(b) 1.55 mm

7D.3 6

7D.4 ml = โ€“4, โ€“3, โ€“2, โ€“1, 0, +1, +2, +3

7D.5 6.65 ร— 10โˆ’22 J

Topic 7E Vibration

7E.1 0.04 N mโˆ’1

7E.2 6.90 ร— 1013 sโˆ’1

7E.3 7.94 ร— 10โˆ’6 N mโˆ’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 ร— 10โˆ’4 N

(b) 6.1 ร— 10โˆ’10 Pa

(c) 1600 s

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7.5 ๐‘ฅ = ยฑ0.5887/๐‘Ž1/2

7.7 (a) 1.8 ร— 10โˆ’4

(b) 5.9 ร— 10โˆ’5

7.8 5h2 / 8mL

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

5h2 / 4mL

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

7.9 ๐ฟ/4 , 3๐ฟ/4

7.10 (a) 2.2 ร— 10โˆ’20 J

(b) 9.2 ฮผm

7.12 (a) 0.22

(b) 9.5 ร— 10โˆ’3

7.13 8.79 ร— 1011sโˆ’1

7.14 2.10 ร— 10โˆ’22 J

7.15 0.707

Answers to projects

7.1 (a) ๐‘ฅ = 0.1 to ๐‘ฅ = 0.2 nm:

๐‘ƒ(๐‘ฅ) = 1.84 ร— 10โˆ’4, 3.8 per cent

x = 4.9 to x = 5.2 nm:

๐‘ƒ(๐‘ฅ) = 2.36 ร— 10โˆ’4, 74.9 per cent

(b) 0.196

(c) 0.609

(d) 0.196

7.2 (a) (i) ๐œ“(๐‘ฅ) = (๐‘Ž/ฯ€)1/4eโˆ’๐‘Ž๐‘ฅ2/2

(ii) x = 0

(b) (i) ๐œ“(๐‘ฅ) = (4๐‘Ž3/ฯ€)1/4๐‘ฅeโˆ’๐‘Ž๐‘ฅ2/2

(ii) x = ยฑ1/a1/2

7.3 (a) 6.432 ร— 1013 sโˆ’1

(b) 2146 cmโˆ’1

(c) ๐œˆ C13 O16 2098 cmโˆ’1

๐œˆ C12 O18 2094 cmโˆ’1

๐œˆ C13 O18 2045 cmโˆ’1

Focus 8

Atomic structure

Answers to exercises

Topic 8A Hydrogenic atoms

8A.1 4.10296 ร— 10โˆ’5cm = 410.296 nm

8A.2 ๐‘›2 = 5

8A.3 ๐‘›2 = 6

8A.4 1.00047

8A.5 27 cmโˆ’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) 61/2โ„, 2 angular nodes,

0 radial nodes

(d) 21/2โ„, 1 angular node, 0 radial nodes

(e) 21/2โ„, 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) (๐‘› ๐‘™ 1)

(b) l

(c) (๐‘› 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 molโˆ’1

Topic 8D Atomic spectroscopy

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

8D.3 nd, ng

8D.4 (a) ๐ฟ = 2, 1, 0

(b) ๐ฟ = 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

๐ฝ = 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 cmโˆ’1

He4 + 15239.3 cmโˆ’1

n = 2 1: He3 + 82288.5 cmโˆ’1

He4 + 82292.3 cmโˆ’1

8.2 122.31 eV

8.3 (a) n = 7 6 12368 nm

n = โˆž 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 cmโˆ’1

(b) n = 3 2 137170 cmโˆ’1

n = 4 2 185180 cmโˆ’1

(c) 122.5 eV

8.6 14.0 eV

8.7 0.602 ๐‘Ž0

8.8 (a) 0.262 a0, 2.530 a0

(b) 0.090 a0, 3.845 a0

8.9 (a) 1.4 ร— 10โˆ’5

(b) 1.1 ร— 10โˆ’4

8.10 (a) 1.9 ๐‘Ž0 , 7.10 ๐‘Ž0

(b) 1.87 ๐‘Ž0, 6.61 ๐‘Ž0, 15.5 ๐‘Ž0

8.11 Fe2+

8.12 2.142 meV

Answers to projects

8.1 (a) ๐‘Ÿ = ๐‘Ž0

(b) (i) 2.69 ร— 10โˆ’7

(ii) 2.47 ร— 10โˆ’8

(iii) 0

(c) 5.24 a0

(d) 5.236 ๐‘Ž0

8.3 (a) receding, 338 km sโˆ’1

Focus 9

The chemical bond

Answers to exercises

Topic 9A Valence bond theory

9A.1 1870 kJ molโˆ’1

9A.2 ๐œ“Cโˆ’H = ๐œ“C(1)๐œ“H(2) + ๐œ“C(2)๐œ“H(1)

9A.3 ๐œ“1(ฯƒ-bond) =

๐œ“2p๐‘งA(1)๐œ“2p๐‘งB(2) + ๐œ“2p๐‘งA(2)๐œ“2p๐‘งB(1)

๐œ“2(ฯ€-bond) =

๐œ“2p๐‘ฅA(1)๐œ“2p๐‘ฅB(2) + ๐œ“2p๐‘ฅA(2)๐œ“2p๐‘ฅB(1)

๐œ“3(ฯ€-bond) =

๐œ“2p๐‘ฆA(1)๐œ“2p๐‘ฆB(2) + ๐œ“2pyA(2)๐œ“2p๐‘ฆB(1)

9A.5 210 times

9B.2 F2โˆ’: ยฝ

F2: 1

F2+: 1ยฝ

9B.3 O2+: 2ยฝ

O2: 2

O2โˆ’: 1ยฝ

O22โˆ’: 1

O2+ < O2 < O2

โ€“ < O2

2โ€“

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9B.4

(a) H2โˆ’: 1ฯƒg

21ฯƒu1

(b) Li2: 1ฯƒg2

(c) Be2: 1ฯƒg2 1ฯƒu

2

(d) C2: 1ฯƒg2 1ฯƒu

2 1ฯ€u4

(e) N2: 1ฯƒg2 1ฯƒu

2 2ฯƒg2 1ฯ€u

4

(f) O2: 1ฯƒg2 1ฯƒu

2 2ฯƒg2 1ฯ€u

4 1ฯ€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 โˆ’6.26 eV

604 kJ molโˆ’1

๐Ÿ—๐ƒ.2 6๐›ผ + 8๐›ฝ

9D.3 0

9D.4 (a) โˆ’2๐›ฝ

(b) โˆ’1.24๐›ฝ

(c) โˆ’2๐›ฝ

Answers to problems

9.2 bond angle for SO2 is 120

9.8 CO: 1ฯƒ2 2ฯƒ2 3ฯƒ2 1ฯ€4

NO: 1ฯƒ2 2ฯƒ2 3ฯƒ2 1ฯ€4 2ฯ€1

CNโˆ’: 1ฯƒ2 2ฯƒ2 3ฯƒ2 1ฯ€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 โˆ’30750 cmโˆ’1

butadiene โˆ’37280 cmโˆ’1

hexatriene โˆ’44660 cmโˆ’1

octatetraene โˆ’47370 cmโˆ’1

(b) โˆ’71910 cmโˆ’1

9.14 (a) benzene: ๐›ผ + 2๐›ฝ, ๐›ผ + ๐›ฝ,

๐›ผ + ๐›ฝ, ๐›ผ โˆ’ ๐›ฝ, ๐›ผ โˆ’ ๐›ฝ, ๐›ผ โˆ’ 2๐›ฝ

Cyclooctatetraene:

๐›ผ + 2๐›ฝ, ๐›ผ + โˆš2๐›ฝ, ๐›ผ + โˆš2๐›ฝ,

๐›ผ, ๐›ผ, ๐›ผ โˆ’ โˆš2๐›ฝ, ๐›ผ โˆ’ โˆš2๐›ฝ, ๐›ผ โˆ’ 2๐›ฝ

(b) benzene: 2๐›ฝ

hexatriene: 0.988๐›ฝ

(c) cyclooctatetraene: 1.657๐›ฝ

octatetraene: 1.516๐›ฝ

9.15 ๐›ผ + โˆš2๐›ฝ: bonding

๐›ผ: non โˆ’ bonding

๐›ผ โˆ’ โˆš2๐›ฝ: antibonding

9.16 (a) C6H6โˆ’: 1ฯ€u

2 2ฯ€g4 1ฯ€u

1

7๐›ผ + 7๐›ฝ

(b) C6H6+: 1ฯ€u

2 2ฯ€g3

5๐›ผ + 7๐›ฝ

Answers to projects

9.2 (c) ฯ€/4, โˆ’ฯ€/4

9.3 (b) (๐‘…/๐‘Ž0) = 2.11

(c) ๐œ“1 = ยฑ(0.356๐ด + 0.934๐ต)

๐œ“2 = ยฑ(0.934๐ด โˆ’ 0.356๐ต)

Focus 10

Molecular interactions

Answers to exercises

Topic 10A Electric properties of molecules

10A.1 โˆ’36 J molโˆ’1

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10A.2 (a) 1.78 D, 5.9 ร— 10โˆ’30C m

(b) 0.94 D, 3.1 ร— 10โˆ’30C m

(c) 0.76 D, 2.5 ร— 10โˆ’30C m

10A.3 ๐œ‡/D = โˆ’0.89

10A.4 1.17 D

10A.5 (a) C2 m

2 J

โˆ’1

(b) (C2 m

2 J

โˆ’1) / (C

2 J

โˆ’1 m

โˆ’1) = m

3

Topic 10B Interactions between molecules

10B.1 โˆ’5.22 ร— 10โˆ’24 J

10B.2 ๐‘‰(๐‘Ÿ) = โˆ’1.9 ร— 10โˆ’27 J

๐‘‰m(๐‘Ÿ) = โˆ’1.19 ร— 10โˆ’3 J molโˆ’1

10B.3 479 pm

10B.4 ๐‘Ÿ = 700 pm

๐‘A๐œ– = 12.6 kJ molโˆ’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 ๐œ‡ = 37 D

๐œƒ = 11.8ยฐ

10.5 1.17 ร— 10โˆ’29 C m = 3.50 D

10.7 (a) 476 kJ molโˆ’1

(b) 87.4 kJ molโˆ’1

10.9 (a) 3.72 kJ molโˆ’1

(b) โˆ’0.365 J molโˆ’1

10.10 196 pm

10.11 ๐‘‰(๐‘Ÿ) = โˆ’1.6 ร— 10โˆ’26 J

๐‘‰m(๐‘Ÿ) = โˆ’9.6 ร— 10โˆ’3J molโˆ’1

๐Ÿ๐ŸŽ.12 ๐‘‰(๐‘Ÿ) = โˆ’7.0 ร— 10โˆ’20 J,

๐‘‰m(๐‘Ÿ) = โˆ’42 kJ molโˆ’1

10.14 250 to 410 pm

10.16 (a) 11.6 kJ molโˆ’1

(c) 2.12 ร— 1012 sโˆ’1

Focus 11

Molecular spectroscopy

Answers to exercises

11A.1 (a) 6.78 ร— 1014 Hz

(b) 22600 cmโˆ’1

11A.2 (a) 2.94 ร— 10โˆ’3 cmโˆ’1

(b) 3.41 m

11A.3 (a) 1.48 ร— 104 dm3 molโˆ’1 cmโˆ’1

(b) 0.9506%

11A.4 (a) 55 dm3 molโˆ’1 cmโˆ’1

(b) 0.048

11A.5 659.999936 nm

7.02 ร— 107 m sโˆ’1

11A.6 8.3 ร— 105 K

11A.7 (a) 53 ps

(b) 5.3 ps

(c) 160 ps

11A.8 (a) 53 cmโˆ’1

(b) 0.27 cmโˆ’1

Topic 11B Rotational spectroscopy

11B.1 3.6 ร— 1033

11B.2 (a) (i) 4.601 ร— 10โˆ’48 kg m2

(ii) 9.194 ร— 10โˆ’48 kg m2

(iii), (iv) 7.150 ร— 10โˆ’46 kg m2

(b) (i) 1.824 ร— 1012 Hz

60.84 cmโˆ’1

(ii) 9.126 ร— 1011 Hz

30.44 cmโˆ’1

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(iii), (iv) 1.174 ร— 1010 Hz

0.3915 cmโˆ’1

11B.3 (b) 2.66 ร— 109 sโˆ’1

0.0888 cmโˆ’1

11B.4 ๐ผโŠฅ = 4๐‘šB๐‘ŸB2

๐ผโˆฅ = 2๐‘šB๐‘ŸB2

11B.5 ๐ด = 5.149 GHz

๐ต = 10.30 GHz

11B.6 (a) 289

(b) 17

11B.7 232.1 pm

11B.8 ยฝ

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 cmโˆ’1

11B.14 5990749.416 MHz

11B.15 116.2 pm

11B.16 20643 cmโˆ’1

Topic 11C Vibrational spectroscopy

11C.1 (a) 4.49 ร— 1013 Hz

(b) 4.39 ร— 1013 Hz

11C.2 (a) 3

(b) 4

(c) 48

(d) 54

11C.3 329 N mโˆ’1

11C.4 (a) (i) HF: 967.4 N mโˆ’1

(ii) HCl: 515.8 N mโˆ’1

(iii) HBr: 411.8 N mโˆ’1

(iv) HI: 314.3 N mโˆ’1

(b) DF: 2930 cmโˆ’1

DCl: 2114 cmโˆ’1

DBr: 1874 cmโˆ’1

DI: 1634 cmโˆ’1

11C.6 3724.66 cmโˆ’1

11C.7 ๐‘ฅe = 0.0062

11C.8 2699.9 cmโˆ’1

Topic 11D Electronic spectroscopy

11D.1 [A] = 0.56 mol dmโ€“3

[B] = 0.16 mol dm

โ€“3

11D.2 1.737 ร— 10โˆ’15 J

11D.3 50.8 nm

11D.4 1.602 ร— 10โˆ’15 J

11D.5 (a) 2.04 ร— 10โˆ’19 J

(b) 669 km sโˆ’1

Topic 11E The decay of excited states

11E.2 0.57

11E.3 4.7 nm

Answers to problems

11.1 33 ฮผg dmโˆ’3

11.2 (a) 162 pm

(b) 179 GHz

11.3 (b) 3.2645 GHz

(c) 237.6 pm

11.4 ๏ฟฝฬƒ๏ฟฝ = 0.2029 cmโˆ’1

๏ฟฝฬƒ๏ฟฝ = 6.233 ร— 10โˆ’8 cmโˆ’1

11.5 ROC = 116.28 pm

RCS = 155.97 pm

11.9 (b) 126.5 pm

11.11 ๐‘˜Q = 5.16 ร— 106 molโˆ’1 dm3 sโˆ’1

11.12 kF = 1.276 1010

molโ€“1

dm3 s

โ€“1

11.13 kQ =9.146 109 mol

โ€“1 dm

3 s

โ€“1

๐‘ก1/2 = 0.172 ฮผs

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 ๐ฝmax = (๐‘˜๐‘‡/โ„Ž๐ต)1/2 โˆ’ ยฝ

11.5 2.6 nm

Focus 12

Statistical thermodynamics

Answers to exercises

Topic 12A The Boltzmann distribution

12A.1 ๐‘2

๐‘1= 0.37

12A.2 524 K

12A.3 ๐‘5

๐‘0= 7.4

Topic 12B The partition function

12B.1 (a) ๐“† = 1 + 6eโˆ’2๐œ€/๐‘˜๐‘‡ + 3eโˆ’5๐œ€/๐‘˜๐‘‡

(b) ๐“† = 1

(c) ๐“† = 10

12B.2 (a) ๐“†T = 1.45 ร— 1027

(b) ๐“†T = 6.49 ร— 1027

12B.3 (a) ๐“†T = 3.2 ร— 104

(b) ๐“†T = 6.2 ร— 1027

12B.4 (a) ๐“†R = 19.5

(b) ๐“†R = 265

12B.5 eqn 12B.6: ๐“†V = 1.39

eqn 12B.7: ๐“†V = 0.789

12B.6 ๐“†E = 4.23

Topic 12C The origin of thermodynamic

properties

12C.1 ๏ฟฝฬ…๏ฟฝ = (5eโˆ’๐œ€/๐‘˜๐‘‡+9eโˆ’3๐œ€/๐‘˜๐‘‡

1+5eโˆ’๐œ€/๐‘˜๐‘‡+9eโˆ’3๐œ€/๐‘˜๐‘‡) ๐œ€

12C.2 (a) 1.25 kJ molโˆ’1

(b) 2.08 kJ molโˆ’1

12C.3 โˆ’37.4 kJ molโˆ’1

Answers to problems

12.1 (a) ๐‘4

๐‘2= 1.753

(b) ๐‘4

๐‘2= 2.27

12.2 (a) ๐“†๐‘… = โˆ‘ ๐‘”๐ฝ๐ฝ=0 eโˆ’๐œ€๐ฝ/๐‘˜๐‘‡: ๐“†๐‘… = 24.816,

Using eqn 12B.5: ๐“†R = 24.474

12.4 11350 K

12.5 (a) 1.401 (at 500 K)

(b) 3.147 (at 1000 K )

12.6 1.28 ร— 1034

12.7 (a) qE = 5

(c) 6.730

12.8 (a) ๐“†E = 1.293 (at 10 K )

๐“†E = 7.825 (at 298 K )

12.9 ๐“†V = 2.14

๐‘†m = 14.6 J Kโˆ’1molโˆ’1

๐Ÿ๐Ÿ.10 183.1 J Kโˆ’1molโˆ’1

12.11 (a) S๊‹(Xe) > S

๊‹(Ne)

(b) S๊‹(D2O) > S

๊‹(H2O)

(c) S๊‹(graphite) > S

๊‹(diamond)

12.12 โˆ’54.3 kJ molโˆ’1

12.13 ๐พ = 1.336 ร— 10โˆ’25

12.14 ๐พ = 1.951 ร— 10โˆ’11

Focus 13

Magnetic Resonance

Answers to exercises

Topic 13A Nuclear magnetic resonance

13A.1 (a) Tโˆ’1 Hz

(c) A s kgโˆ’1

13A.2 ๐ธ3/2 = โˆ’1.949 ร— 10โˆ’26 J

๐ธ1/2 = โˆ’6.498 ร— 10โˆ’27 J

๐ธโˆ’1/2 = 6.498 ร— 10โˆ’27 J

๐ธโˆ’3/2 = 1.949 ร— 10โˆ’26 J

13A.3 2.263

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13A.4 (a) 2.9 ร— 10โˆ’5

(c) 7.3 ร— 10โˆ’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 ฮผT

(b) 38 ฮผT

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 ร— 10โˆ’24 J

13C.2 (a) 9.02 ร— 10โˆ’4

(b) 2.7 ร— 10โˆ’3

13C.3 9.25 GHz, 32.4 mm

13C.4 2.0022

13C.5 ๐‘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) ๐ดโ€ฒ = 1.9 Hz

๐ตโ€ฒ = โˆ’1.4 Hz

๐ถโ€ฒ = 6.4 Hz

(b) 109 ยฐ

13.9 2600 sโˆ’1

13.10 64 sโˆ’1

13.12 1

13.13 ๐Ÿ 0.011 mT: 0.0049

๐Ÿ 0.172 mT: 0.0764

๐Ÿ 0.272 mT: 0.1209

๐Ÿ 0.450 mT: 0.2000

๐Ÿ 0.108 mT: 0.0480

๐Ÿ‘ 0.112 mT: 0.0498

Focus 14

Macromolecules and aggregates

Answers to exercises

Topic 14A Biological and synthetic

macromolecules

14A.1 ๏ฟฝฬ…๏ฟฝn = 95 kg molโˆ’1

๏ฟฝฬ…๏ฟฝw = 93 kg molโˆ’1

14A.2 3.4

14A.3 (a) 0.880 ฮผm

(b) 31.1 nm

(c) 12.7 nm

14A.4 ๐‘…c = 2.74 ฮผm

๐‘…rms = 29.1 nm

14A.5 13000

14A.6 โˆ’0.042 J Kโˆ’1molโˆ’1

14A.7 8 aJ

Topic 14B Mesophases and disperse systems

14B.1 5.8 cm

14B.2 23 mN mโˆ’1

14B.3 (a) 1.4 kPa

(b) 0.14 kPa

14B.4 97 mmol mโˆ’2

Answers to problems

14.1 ๏ฟฝฬ…๏ฟฝn = 20 kg molโˆ’1

๏ฟฝฬ…๏ฟฝw = 22 kg molโˆ’1

14.2 ๏ฟฝฬ…๏ฟฝw/๏ฟฝฬ…๏ฟฝn = 1.27

14.4 โ„ฑ = 1.37 pN

14.6 pH = 6.9

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14.7 68 ฮผJ

Answers to projects

14.1 (a) โŸจ๐‘…2โŸฉ1/2 = 10.9 nm

(b) โŸจ๐‘…โŸฉ = 10.0 nm

(c) ๐‘…โˆ— = 8.89 nm

14.3 (a) 2.70 pN

Focus 15

Solids

Answers to exercises

Topic 15A Crystal structure

15A.1 ๐‘‰ = 0.396 nm3

๐œŒ = 2.41 ร— 103kg mโˆ’3

15A.2 ๐‘ = 3.9

๐œŒ = 4.01 ร— 103 kg mโˆ’3

๐Ÿ๐Ÿ“๐€.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 ๐‘Ž = 363 pm

๐‘ = 564 pm

15A.8 112 pm

15A.9 1.28 mV

15A.10 66.1 pm

15A.11 ๐‘Ž = 798 pm

Topic 15B Bonding in solids

15B.1 (a) zinc-blende

(b) zinc blende

(c) rock-salt

15B.2 ฮ”L๐ป๊‹(SrO)

ฮ”L๐ป๊‹(CaO)= 0.947

15B.3 3000 kJ molโˆ’1

Topic 15C The properties of solids

15C.3 549 nm

Answers to problems

15.2 (321). (111). (122). (32ฬ…2ฬ…).

15.6 bcc

15.7 (b) 8.97 ร— 103 kg mโˆ’3

15.8 0.740

15.9 0.740 g cmโˆ’3

15.10 520 nm

15.11 (a) 424 nm

(b) 600 nm

15.12 (a) less dense

(b) 92 per cent

15.15 ๐‘‰ = โˆ’๐‘๐‘ง2๐‘’2ฯ€

48๐œ€0๐‘‘

15.16 โˆ’8.16 ร— 10โˆ’18 J

15.18 +3500 kJ molโˆ’1

15.19 +2421 kJ molโˆ’1