Question

A mole of a monatomic ideal gas is taken from an initial pressure p and volume V to a final pressure 3p and volume 3V by two different processes: (I) It expands isothermally until its volume is tripled, and then its pressure is increased at constant volume to the final pressure. (II) It is compressed isothermally until its pressure is tripled, and then its volume is increased at constant pressure to the final volume. Show the path of each process on a p-V diagram. For each process calculate, in terms of p and V, (a) the heat absorbed by the gas in each part of the process, (b) the work done by the gas in each part of the process, (c) the change in internal energy of the gas, Uint, f – Uint, i, and (d) the change in entropy of the gas, Sf – Si. (20%)

Answer 1