The degree of dissociation `(alpha)` of a weak electrolyte `A_(x)B_(y)` is related to van't Hoff factor (i) by the expression

Options

A. `alpha = (i - 1)/((x + y -1))`
B. `alpha = (i-1)/(x + y + 1)`
C. `alpha = (x + y - 1)/(i-1)`
D. `alpha = (x + y + 1)/(i - 1)`

Answer

A

Explanation

`A_(x) B_(y) rArr xA^(+) + yB^(-)`
`1 - alpha x alpha y alpha`
Total `= 1 + alpha (x + Y - 1) or `i = 1 + alpha (x + y -1)` or `alpha = (i-1)/(x + y - 1)`