$\mathrm{H}_2 \mathrm{~S}$ (5 moles) reacts completely with acidified aqueous potassium permanganate solution. In this reaction, the number of moles of water produced is $\mathbf{x}$, and the number of moles of electrons involved is $\mathbf{y}$. The value of ( $\mathbf{x}+ y$ ) is $\_\_\_\_$ .
