Question
Predict the products of electrolysis in each of the following:
A dilute solution of H2SO4with platinum electrodes.
Solution
At the cathode, the following reduction reaction occurs to produce H2 gas.
`H_(" "(aq))^+ + e^(-) -> 1/2 H_(2(g))`
At the anode, the following processes are possible
`2H_2O_(l) ->O_(2(g)) + 4H_(" "(aq))^(+) + 4e^(-); E^@ = +1.23 V` ....(i)
`2SO_(4(aq))^(2-) -> S_2O_(6(aq))^(2-) + 2e^(-); E^@ = + 1.96 V`.... (ii)
For dilute sulphuric acid, reaction (i) is preferred to produce O2 gas. But for concentrated sulphuric acid, reaction (ii) occurs.
Is there an error in this question or solution?
Solution Predict the products of electrolysis in each of the following: A dilute solution of H2SO4with platinum electrodes. Concept: Electrolytic Cells and Electrolysis - Introduction.
