\( \mathrm{H_2S} \) \( (\,5\, \text{moles}\,) \) reacts completely with acidified aqueous potassium permanganate solution. In this reaction, the number of moles of water produced is \( x \), and the number of moles of electrons involved is \( y \). The value of \( (x + y) \) is \( \_\_\_\_\_\_\_\_ \).
