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R6.12 For nonmetallic solids at very low T, C p,m is propor- R6.15 For a substance that is a liquid at 25°C and 1 bar and
3
tional to T . If C° P,m is 0.54 J mol 1 K 1 at 6.0 K for a certain that has only one solid form, sketch the conventional standard
substance, find the conventional standard molar entropy of that molar entropy versus temperature from 0 K to 298 K.
substance at 4.0 K.
R6.16 For each of the following systems, write the material-
R6.13 (a) Write the expression for the chemical potential of a equilibrium condition(s) in terms of chemical potentials.
component of an ideal gas mixture. (b) Write the expression (a) Solid sucrose in equilibrium with an aqueous solution of
found in Chapter 4 as the equilibrium condition for the reac- sucrose and KCl. (b) A system with the equilibrium 2NO(g)
tion 0 S i v i A i . (c) Substitute the expression in (a) into the O (g) ∆ 2NO (g).
2 2
equilibrium condition in (b) and derive the relation between
R6.17 Use Appendix data to find H° for the reaction
G° and K° for an ideal-gas reaction. 360
P
2NO(g) O (g) S 2NO (g), and state any approximation
2
2
R6.14 (a) Give the Kelvin–Planck statement of the second made. (Do not assume that H° is independent of T.)
law. (b) Give the Nernst–Simon statement of the third law.