For a reaction X + Y ⇌ 2 Z, 1.0 mol of X, 1.5 mol of Y and 0.5 mol of Z were taken in a 1 L vessel and allowed to react. At equilibrium, the…

For a reaction $\displaystyle \mathrm{X}+\mathrm{Y} \rightleftharpoons 2 \mathrm{Z}, 1.0 \mathrm{~mol}$ of X , $\displaystyle 1.5$ mol of Y and $\displaystyle 0.5$ mol of Z were taken in a $\displaystyle 1$ L vessel and allowed to react. At equilibrium, the concentration of Z was $\displaystyle 1.0 \mathrm{~mol} \mathrm{~L}^{-1}$. The equilibrium constant of the reaction is \_\_\_\_ $\displaystyle \frac{x}{15}$. The value of $\displaystyle x$ is \_\_\_\_.