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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:
B
`K _(a) = ([ H ^(o+) ] [overset(o+)(OH)] )/([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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