The `K_(a)` for formic acid and acetic acid are `2.1 xx 10^(-4)` and `1.1 xx 10^(-5)`, respectively. Calculate relative strength of acids

Explanation

Relative strength of weak acids `= sqrt((K_(a_(1)))/(K_(a_(2)))) xx (C_(1))/(C_(2))`
Assume `C_(1)` and `C_(2)` are same (although not given).
`:.` Relative strength `= sqrt((K_(a_(1)))/(K_(a_(2)))) = sqrt((2.1 xx 10^(-4))/(1.1xx10^(-5)) = 4.36:1`
Relative strength for `HCOOH` to `CH_(3)COOH = 4.36:1`