In a fuel cell, hydrogen and oxygen react to produce electricity. In process, hydrogen gas is oxidized at the anode and oxygen at the cathode. If `67.2L` of `H_(2)` at `STP` reacts in `15mi n` , what is the average current produced ? If the entire current is used for electro`-` deposition of copper from copper `(II)` solution, how many grams of copper will be deposited ?
Anode reaction `: H_(2)+2overset(c-)(O)Hrarr2H_(2)O+2e^(-)`
Cathode reaction `:O_(2)+2H_(2)O+2e^(-) rarr 4overset(c-)(O)H`

Explanation

We know
Moles of `H_(2)` reacting `= (67.2)/(22.4) = 3`
`:.` Eq. of `H_(2)` used `= 3 xx 2 = 6`
Now `(w)/(E) = (i.t)/(96500), 6 = (i xx 15 xx 60)/(96500)`
`:. i = 643.33`
Also Eq. of `H_(2)` = Eq. of `Cu` formed `:.` Eq. of `Cu` deposited `= 6`
`w_(Cu) = 6 xx (63.5)/(2) = 190.5 g`
`Wt.` of `Cu` deposited `= 190.5 g`