Question

Resistance of 2 M solution of an electrolyte is $50\text{ }\Omega$. The conductivity of the solution is $3\text{ S m}^{-1}$. If the resistance of 4 M solution of the same electrolyte is $260\text{ }\Omega$, its molar conductivity is:

• A. $6.25 \times 10^{-3}\text{ S m}^2\text{ mol}^{-1}$
• B. $6.25 \times 10^{-4}\text{ S m}^2\text{ mol}^{-1}$
• C. $625 \times 10^{-4}\text{ S m}^2\text{ mol}^{-1}$
• D. $62.5 \times 10^{-4}\text{ S m}^2\text{ mol}^{-1}$

Hint:

To ensure your units track correctly in SI calculations, remember that converting concentration from $\text{mol/L}$ to $\text{mol/m}^3$ requires multiplying by $1000$. This places $1000$ in the denominator, yielding $\frac{0.25}{400} = 6.25 \times 10^{-4}\text{ S m}^2\text{ mol}^{-1}$.

Answer 1

The Correct Option is B