Problem 2.187

The saturated water vapour is enclosed in a cylinder under a piston and occupies a volume $V_{0}=5.0 \mathrm{l}$ at the temperature $t$ $=100^{\circ} \mathrm{C} .$ Find the mass of the liquid phase formed after the volume under the piston decreased isothermally to $V=1.61 .$ The saturated vapour is assumed to be ideal.