Question

Solutions of two electrolytes ‘A’ and ‘B’ are diluted. The λm of ‘B’ increases 1.5 times while that of A increases 25 times. Which of the two is a strong electrolyte? Justify your answer. Graphically show the behavior of ‘A’ and ‘B’.

Answer 1

\(\lambda m\) represents molar conductivity. It is the conducting power of ions due to one mole of electrolyte in a solution.

\(\lambda m= \frac{\text{specific conductance } \times \,100}{\text{Molarity}}\)

A strong electrolyte would diffuse into ions at the first dissolution.

There would be no increase in the number of ions on dilution as strong electrolytes are completely dissociated.

Hence, \(\lambda m\) would remain constant/change slowly on dilution.

B is a strong electrolyte.

Answer 2

B is a strong electrolyte. The molar conductivity increases slowly with dilution as there is no increase in number of ions on dilution as strong electrolytes are completely dissociated.