`100mL` of buffer of `1 M NH_(3)(aq)` and `1 M NH_(4)^(o+)(aq)` are placed in two compartments of a voltaic cell separately. A current of `1.5A` is passed through both cells for `20 m i n`. If only electrolysis of water takes place, then

Options

A. `pH` of `LHE` half celll will increase
B. `pH` of `RHE` half cell will increase
C. `pH` of both half cell will increase
D. `pH` of both half cell will decrease

Answer

B

Explanation

Cathode `(RHE):2H_(2)O(l)+2e^(-) rarr H_(2)(g)+2OH(aq)`
Anode `(LHE):2H_(2)o(l) rarr O_(2)(g)+4H^(o+)(aq)+4e^(-)`
In RHE, `overset(c-)(O)H` will be produced which will react with `NH_(4)^(o+)(` salt `)` to form `NH_(4)OH(` base `)` , causing `pOH` to decrease or `pH` to increase.
In `LHE,H^(o+)` will be produced with will react with `NH_(4)OH(` base `)` to form `NH_(4)^(o+)(` salt `)`, causing `pOH` to incdrease or `pH` to decrease.