An aqueous solution of `NaCl` on electrolysis gives `H_(2)(g), Cl_(2)(g),` and `NaOH` accroding to the reaction `:`
`2Cl^(c-)(aq)+2H_(2)Orarr2overset(c-)(O)H(aq)+H_(2)(g)+Cl_(2)(g)`
A direct current of `25A` with a current efficiency of `62%` is passed through `20L` of `NaCl` solution `(20%` by weight`)`. Write down the reactions taking place at the anode and cathode. How long will it take to produce `1 kg ` of `Cl_(2)`? `(` Assume no loss due to evaporation . `)`

Answer

`48.71 hour, [OH^(-)] = 1.41M`

Explanation

`2NaCI hArr 2Na^(+) +2CI^(-)`
`2H_(2)O hArr 2H^(+) +2OH^(-)`
At anode:
`2CI^(-) rarr CI_(2) +2e^(-)`
At anode:
`2H^(+) +2e^(-) rarr H_(2)`
Not reaction
`2NaCI + 2H_(2)O hArr 2OH^(-) +H_(2) + CI_(2) +2Na^(+)` ltbr. `100 = (35.5)/(96500) xx 25.62 xx t`
`t = 175374.83 sec = 48.74 hr`.
moles of `OH^(-) = (1000)/(71) xx2`
volume `= 20L`
`[OH^(-)] = (2000)/(71 xx 20) = 1.408M`