The degree of dissociation of weak electrolyde is inversely proportional to the square root fo concentration. It is called Ostwald's dilution law.
`alpha = sqrt((K_(a))/(c))` As the tempertaure increases, degree of dissociation will increase.
`(alpha_(1))/(alpha_(2)) = sqrt((K_(a_(1)))/(K_(a_(2))))` if concentration is same.
`(alpha_(1))/(alpha_(2)) = sqrt((c_(2))/(c_(1)))` if acid is same.
`a_(1)` and `a_(2)` are in ratio of `1:2, K_(a_(1)) = 2xx10^(-4)`. What will be `K_(a_(2))`?

Options

A. `8 xx 10^(-4)`
B. `2xx10^(-4)`
C. `4 xx 10^(-4)`
D. `1xx10^(-4)`

Answer

A

Explanation

`(alpha_(1))/(alpha_(2)) = (1)/(2) = sqrt((K_(a_(1)))/(K_(a_(2)))) rArr 4K_(a_(1)) = 8 xx 10^(-4)`