Question

A conductance cell was filled with a 0.02 M KCl solution which has a specific conductance of $2.768\times {10}^{-3}oh{m}^{-1}c{m}^{-1}$. If its resistance is 82.4 ohm at ${25}^o$C, then the cell constant is:

• A. 0.2182 $c{m}^{-1}$
• B. 0.2281 $c{m}^{-1}$
• C. 0.2821 $c{m}^{-1}$
• D. 0.2381 $c{m}^{-1}$

Answer 1

The correct option is B 0.2281 $c{m}^{-1}$

The specific conductance $\left(\kappa \right)$ is the product of cell constant $\left(\frac{l}{a}\right)$ and reciprocal of resistance $\left(\frac{1}{R}\right)$.

Hence, $\frac{l}{a}=\kappa \times R=2.768\times {10}^{-3}{ohm}^{-1}{cm}^{-1}\times 82.4ohm=0.2281{cm}^{-1}$.

Hence, option $B$ is correct.