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2H (2) O hArr H (3) O ^(o+) + overset(o+...

`2H _(2) O hArr H _(3) O ^(o+) + overset(o+) (OH), K _(w) = 10 ^(=14) at 25 ^(@)C,` hence `K _(a)` is

A

`10^(-7)`

B

`5.55 xx 10^(-13)`

C

`10^(-14)`

D

`18 xx 10^(-17)`

Text Solution

Verified by Experts

The correct Answer is:
D
`K_(a) = ([H^(o+)][overset(ɵ)(O)H])/([H_(2)O]) = (K_(w))/([H_(2)O]) = (10^(-14))/(55.6) = 18 xx 10^(-17)` (M of `H_(2)O = 55.6`)
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