Problem 2.5

A vessel of volume $V=7.5$ l contains a mixture of ideal gases at a temperature $T=300 \mathrm{~K}: v_{1}=0.10$ mole of oxygen, $v_{2}=0.20$ mole of nitrogen, and $v_{3}=0.30$ mole of carbon dioxide. Assuming the gases to be ideal, find: (a) the pressure of the mixture; (b) the mean molar mass $M$ of the given mixture which enters its equation of state $p V=(m / M) R T,$ where $m$ is the mass of the mixture.