Chapter 2:
                        3, 8, 9, 10, 11, 15, 16, 48

Hints/comments:

2.11: go ahead and use the ideal gas equation of state for the vapor

2.48: you need to integrate C(T)dT from T=0 to T=298.15 K for this problem. This means you'll have to fit the C(T) data so that you can integrate the resulting function with a program like MathCAD or Mathematica. Note that you'll need to constrain the region from 0 to 10 K to obey a cubic function, namely set C(T) = a(T/10K)³ in this region, where a is the experimental C at 10 K.