Home
Class 12
CHEMISTRY
The K(a) value of formic acid and acetic...

The `K_(a)` value of formic acid and acetic acid are respectively `1.77 xx 10^(-4)` and `1.75 xx 10^(-5)` . The ratio of the acid strength of 0.1 N acids is

Text Solution

Verified by Experts

The correct Answer is:
3.18
`(3.18) HA hArr H^(+) + A^(-) , K_(a) = ([H^+][A^-])/([HA])`
Let C `moL^(-1)` be the conc. And `alpha` its degree of dissociation
`therefore K_a = (C alpha xx C alpha)/(C(1-alpha)) = C alpha^2` (when `alpha` is very small)
`therefore a = sqrt((K_a)/(C))` when C is constant, `[H^+] prop alpha`
`therefore (alpha_1)/(alpha_2) = sqrt((K_(a1))/K_(a2)) = sqrt((1.77 xx 10^(-4))/(1.75 xx 10^(-5)))`
`= sqrt(10) ~~ 3.18`
Promotional Banner

Similar Questions

Explore conceptually related problems

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

K_(a) for formic acid and acetic acid are 2.1xx10^(-4) and 1.1xx10^(-5) respectively. The relative strength of acids is:

Dissociation constant (K_a) of formic acid and acetic acid are 2.5xx10^-4 and 0.5xx10^-5 respectively. The ratio of their relative strengths at the same concentration is

The K_(a) for formic acid and acetic acid are 2xx10^(-4) and 2xx10^(-5) respectively. Calculate the relative strength of acids with same molar concentration

At certain temperature, dissociation constant of formic acid and acetic acid are 1.8xx10^(-4) and 1.8xx10^(-5) respectively. At what concentration of acetic solution, the H_93)O^(+) ion concentration is same as that in 0.001 M formic acid solution