According to the following reaction the minimum quantity in gm of `H_(2)S` needed to precipitate 63.5gm of `Cu^(2+)` ions will be nearly:
`Cu^(2+) + H_(2)S rArr CuS + 2H^(+)`

Options

A. 63.5 gm
B. 31.75 gm
C. 34 gm
D. 20 gm

Answer

C