Q. For the reaction $N _{2}+3 H _{2} \rightleftharpoons 2 NH _{3}, N _{2}$ and $H _{2}$ were taken in the molar ratio of $1: 3$. Up to the point of equilibrium $50 \%$ each reactant has been reacted. If total pressure at equilibrium is $P$. The partial pressure of ammonia would be
Equilibrium
Solution: