Physical Chemistry Third Edition

1320 K Answers to Numerical Exercises and Odd-Numbered Numerical Problems

Chapter 6 Problems

6.5
∆Smix 22 .00JK−^1
∆Gmix−6560 J
∆Hmix 0
∆Umix 0

6.11
∆S 9 .464JK−^1

6.13
M 2  127 .9 g mol−^1

6.15
a. K
(c)
d ^0.^012
b. Vthio 4 .5mL

6.17
k
(u)
2 2380 torr

6.19
x 1. 40 × 10 −^4

6.21
a 1  0. 99955

6.23
γ
(m)
2 ^0.^9275
γ
(c)
2 ^1.^036

6.25
γ 1. 0044

6.27
a. k 2  0 .689 atm
b. P 2  0 .754 atm

c.Atx 2  0. 0500 : γ

(II)

2 ^1 .00,a

(II)

2 ^0.^05

γ

(I)

2 ^0 .914,a

(I)

2 ^0.^0457

Atx 2  0. 600 : γ 2 (II) 1 .052,a(II) 2  0. 631

γ

(I)

2 ^0 .962,a

(I)

2 ^0.^577

Atx 2  0. 950 : γ

(II)

2 ^1 .094,a

(II)

2 ^1.^039

γ

(I)

2 1,a

(I)

2 ^0.^950

6.29
a. ∆Hdiff◦ (KOH)− 57 .61 kJ mol−^1
b. μ◦(m)(KOH,aq)−G∗m(KOH,s)− 61 .43 kJ mol−^1

6.35
a. α 3 .89 kg^1 /^2 mol−^1 /^2
β 4. 53 × 109 kg^1 /^2 mol−^1 /^2 m−^1

b. For methanol,γ± 0. 710

For water,γ± 0. 899

percent difference−21%

6.39

a. a(I) 1  0. 669

γ

(I)

1 ^0.^944

a

(I)

2 ^0.^1892

γ

(I)

2 ^0.^650

b. ∆Gmix−1973 J

GE−427 J

c.a

(II)

2 ^0.^382

γ

(II)

2 ^1.^31

6.41

a. ac 0 .381,γc 0. 771

aa 0 .394,γa 0. 779

b. ∆Gmix−1777 J

6.43

a. ∆Hmix 38 .97 J

∆Gmix−552 J

b. ∆H 46 .0J

∆G−399 J

6.45

a. γ 2  2 .978,γ 1  1. 312

b. ∆Gmix− 452 .5J

6.47

a. aA 0 .669,γA 0. 944

aC 0 .1982,γC 0. 650

b. ∆Gmix−1938 J

c.aC 0 .382,γC 1. 31

6.49

∆Hdiff− 20 .28 kJ mol−^1

6.63

x(60◦C) 0. 637

6.65

∆T 0 .0748 K

6.67

a. ∆Tb 0 .0788 K

b. ∆Tb 0 .0786 K (0.3% difference)

c. ∆Tb 0 .0789 K (0.1% difference)

6.69

M 2  16 .9kgmol−^1