Question

The equivalent conductivity of $N/10$ solution of acetic acid at $25^{\circ}C$ is $14.3 \,ohm^{-1}\, cm^2 \,equiv^{-1}$. What will be the degree of dissociation of acetic acid ?
$\left(\Lambda_{\infty\,CH_3COOH}=390.71\,ohm^{-1}\,cm^{2}\,equiv^{-1}\right)$

• A. $3.66\%$
• B. $3.9\%$
• C. $2.12\%$
• D. $0.008\%$

Answer 1

Answer: (A)

$\Lambda^{\infty}_{m\,CH_3COOH}=390.71\,ohm^{-1}\,cm^{2}\,equiv^{-1}$
$\Lambda_{CH_3COOH}=14.3\,ohm^{-1}\,cm^{2}\,equiv^{-1}$
Degree of dissociation $\left(\alpha\right)$
$=\frac{\Lambda^{c}_{m}}{\Lambda^{\infty}_{m}}=\frac{14.3}{390.71}$
$=0.0366$ i.e. $3.66\%$