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In two vessels each containing 500 ml wa...

In two vessels each containing 500 ml water, 0.5m mol of aniline (`K_(b)=10^(-9))` and 25 m mol of HCl are added separately. Two hydrogen electrodes are constructed using these solutions. Calculate the emf of cell made by connecting them appropriately.

Text Solution

Verified by Experts

The correct Answer is:
`E = 0.395V`
For aniline
`K_(b) = calpha^(2)`
`10^(-9) = 10^(-3) alpha^(2)`
`alpha^(2) = 10^(-6)`
`alpha = 10^(-3)`
`[OH]^(-) = 10^(-3) xx 10^(-3) = 10^(-6)`
`[H^(+)] = 10^(-8)`
`[H^(+)] = (25)/(500)`
`[H^(+)] rArr 5 xx 10^(-2)`
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