Answer
4.51 atm
Work Step by Step
$n(H_{2})=\frac{1.50\,g}{2.016\,g/mol}=0.744\,mol$
$n(N_{2})= \frac{5.00\,g}{28.0134\,g/mol}=0.178\,mol$
$n_{total}=n(H_{2})+n(N_{2})=(0.744+0.178)mol=0.922\,mol$
$P_{total}=\frac{n_{total}RT}{V}$
$=\frac{(0.922\,mol)(0.0821\,L\,atm\,mol^{-1}K^{-1})(298\,K)}{5.0\,L}$
$=4.51\,atm$