Question

Specific conductance of $0.2M$ aqueous solution is $16.4\times {10}^{-2}oh{m}^{-1}c{m}^{-1}$. The molar conductance of solution is

• A. $315oh{m}^{-1}c{m}^{2}mo{l}^{-1}$
• B. $1201oh{m}^{-1}c{m}^{2}mo{l}^{-1}$
• C. $820oh{m}^{-1}c{m}^{2}mo{l}^{-1}$
• D. $519oh{m}^{-1}c{m}^{2}mo{l}^{-1}$

Answer 1

The correct option is C $820oh{m}^{-1}c{m}^{2}mo{l}^{-1}$

$\text{Molar concentration,}\left(C\right)=0.2M$
$\text{Conductivity,}\kappa =16.4\times {10}^{-2}oh{m}^{-1}c{m}^{-1}$
$\text{Molar conductance,}{\Lambda }_m=\frac{K}{C}$
Also, we know
$1L=1000c{m}^3$
$1L^{-1}={10}^{-3}c{m}^{-3}$
$\text{Molar concentration,}\left(C\right)=0.2mol{L}^{-1}$
$\text{Molar concentration,}\left(C\right)=0.2\times {10}^{-3}molc{m}^{-3}$

$\text{Molar conductance,}{\Lambda }_m=\frac{16.4\times {10}^{-2}}{0.2\times {10}^{-3}}$
$\text{Molar conductance,}{\Lambda }_m=8.2\times {10}^{2}oh{m}^{-1}c{m}^{2}mo{l}^{-1}$