KINETIC THEORY

( atm = . × Pa) occupies a volume of . litres. This universal volume is called molar volume.

Thus the cylinder in this example contains mol of helium. Further, since helium is monatomic, its predicted (and observed) molar specific heat at constant volume, Cv = ( / ) R, and molar specific heat at constant pressure, Cp = ( / ) R + R = ( / ) R. Since the volume of the cylinder is fixed, the heat required is determined by Cv. Therefore, Heat required = no.

. . Specific Heat Capacity of Solids We can use the law of equipartition of energy to determine specific heats of solids. Consider a solid of N atoms, each vibrating about its mean position.

An oscillation in one dimension has average energy of × ½ kBT = kBT . In three dimensions, the average energy is kBT. For a mole of solid, N = NA, and the total energy is