Question

A conductance cell when filled with 0.5 M KCl solution (specific conductance = $6.67\times {10}^{-3}{\Omega }^{-1}c{m}^{-1}$) registers a resistance of $243\Omega$. Its cell constant is:

• A. 1.62 cm
• B. 1.62 $c{m}^{-1}$
• C. 1.62 $d{m}^{-1}$
• D. 1.62 $m^{-1}$

Answer 1

Answer: (A)

1.62 cm

Given:-

Specific conductance $K=6.67\times {10}^{-3}Sc{m}^{-1}$

Concentration= $0.5M$

Resistance= $243\Omega$

Cell constant= $\left(\frac{l}{A}\right)$

$K=G\times \left(\frac{l}{A}\right)$

Conductivity= Conductance $\times$ Cell constant

Conductance= $\frac{1}{Resistance}$

$\Rightarrow 6.67\times {10}^{-3}=\frac{1}{243}\times$ Cell constant

$\Rightarrow$ Cell constant= $1.620cm$