Question

The measured resistance of a conductance cell was $100\Omega$. If the specific conductance in $oh{m}^{-1}c{m}^{-1}$ is $125\times {10}^{-x}$, then what is the value of $x$?
Given:
$(M_{KCl}=74.5gmo{l}^{-1}$
$\text{Cell constant}=1.25c{m}^{-1}$)

• A. 7
• B. 6
• C. 5
• D. 4

Answer 1

The correct option is D 4

The expression for specific conductance is:
$\kappa =\frac{\frac{l}{a}}{R}$
Here,
$R$ is the resistance and $\frac{l}{a}$ is the cell constant.
Substituting the values in the above expression,
$\kappa =\frac{1.25c{m}^{-1}}{100\Omega }=0.0125=125\times {10}^{-4}oh{m}^{-1}c{m}^{-1}$
So, the value of x is 4