Question

The limiting molar conductivity and molar conductivity of acetic acid are $390.5s.c{m}^2.mo{l}^{-1}$ and $48.15s.c{m}^2.mo{l}^{-1}$ respectively. Calculate the degree of dissociation of the weak acid?

• A. $1.233$
• B. $12.33$
• C. $0.1233$
• D. $0.01233$

Answer 1

The correct option is C $0.1233$

The degree of dissociation is give by the following relation:

$\alpha =\frac{{\Lambda }_m}{{\Lambda }_0}$

Where $\alpha$ is the degree of dissociation, ${\Lambda }_m$ is the molar conductivity and ${\Lambda }_0$ is the molar conductivity at infinite dilution i.e. limiting molar conductivity

on substitution we get:

$\alpha =\frac{48.15}{390.5}$

$\alpha =0.1233$

option C is correct