Physical Chemistry , 1st ed.

Chapter 1

1.2.A system is a part of the universe under observation. A
closed system is a system that does not allow for transfer of
matter to or from the surroundings. Energy, however, can
transfer between surroundings and a closed system.

1.3. (a)1.256  104 cm^3 (b)318 K (c)1.069  105 Pa
(d)1.64 bar (e)125 cm^3 (f)268.9°C (g)0.2575 bar

1.4. (a)0°C is the higher temperature. (b)300 K (c)20°C

1.6.F(T) 0.164 Latm; V0.164 L.

1.7.F(p) 1.04  10 ^4 KL; T643 K.

1.12. (a)ptot1.25 atm (b)pHe0.250 atm, pNe
0.100 atm (c)xHe0.200, xNe0.800

1.13.pN 2 11.8 lb/in^2 , pO 2 2.94 lb/in^2

1.14.0.0626 g CO 2 per cm^3

1.15. (a)5 and 5 (b)25 and 55 (c)0.28 and 0.07,
respectively

1.16. (a) 3 y^2 y

2

w

z^3 (b) 3

3

w

2

2

y

z^3 xy

w

2

2

z^3

(c) 6 xyw
32

(^3) z
y^2
3
xy
w
z^3 (d)^3 y
w
(^2) z 2

1.17. (a)npR 2 T(b)RpT(c)npR(d)nVR(e)RVT
1.18.Ris a constant, not a variable.
1.19.pVT
n,pn,V
or VTp
n,Vn,p
1.21.TB(CO 2 ) 1026 K, TB(O 2 ) 521 K, TB(N 2 ) 433 K
1.23.Units on Care L^2 ; units on C are L/atm (for molar
quantities).
1.25.In order of higher to lower predicted ideality: He, H 2 ,
Ne, N 2 , O 2 , Ar, CH 4 , CO 2
1.26.a2.135  105 barcm^6 /mol^2. The cm^6 unit comes
from the fact that 1 L 1000 cm^3 , and there is an L^2 term in
the original unit for a.
1.27.Under “normal” conditions of about 1 atm pressure
and 25°C, V(gas) is approximately 24,500 cm^3. Therefore, the
B/Vterm is about 6.1  10 ^4 for H 2 , increasing its compress-
ibility by about 0.06%. For H 2 O, the compressibility is de-
creased by about 4.6%, an easily noticeable deviation from
ideality.
1.30.Nitrogen’s Boyle temperature is very close to room tem-
perature, implying that its second virial coefficient Bis close to
zero. Therefore, N 2 would be expected to act close to ideally
at room temperature.
1.32.pp
T
 , according to the cyclic rule. However,
it makes no sense to take the derivative with respect to a vari-
able being held constant, so no useful information can be ob-
tained from this expression. The original expression is also
mathematically useless, since we typically must find the varia-
tion in pwith respect to variables other than itself.
1.33. has units 1/(pressure), like 1/atm or 1/bar. has units
1/(temp), or 1/K.
Chapter 2
2.1. (a)900 J (b)640 J
2.3.0.932 Latm or 94.4 J
2.4.3.345 Latm or 338.9 J
2.6.c0.18 J/(g°C)
2.8.Final temperature 24.4°C



T
pp









T

pp

806

Answers to Selected Exercises