Question

Given that the electrolytic conductivity of a solution containing 3g of calcium chloride in 250cm^-3 aqueous solution is 1.6x10^-3 Sm^-1 at 20°C. Calculate the molar conductivity of the solution at 20°C.

Answer 1

Number of moles = $\frac{M_{given}}{M_{molecular}}$

$= \frac{3}{111}$

= 0.027 mol

Molarity = (Number of Moles)/Volume

= $\frac{0.027}{0.25}$

= 0.108 molL^-1

Molar Conductivity = $\kappa$ /(1000 $\times$ Molarity in molL^-1)

= $\frac{1.6\times10^{-3}}{1000\times0.108}$

= 1.48 $\times$ 10^-5 Sm²mol^-1