Ncert Exercises & Solutions

Assertion (A):	Λ_m for weak electrolytes shows a sharp increase when the electrolytic solution is diluted.
Reason (R):	For weak electrolytes degree of dissociation increases with a dilution of the solution.

1.	Both (A) and (R) are True and (R) is the correct explanation of (A).
2.	Both (A) and (R) are True but (R) is not the correct explanation of (A).
3.	(A) is True but (R) is False.
4.	Both (A) and (R) are False.

Hint: For weak electrolytes degree of dissociation directly proportional to the dilution

Molar conductivity of weak electrolytic solution increases on dilution, because as we add excess water to increase the dilution

degree of dissociation increases which leads to an increase in the number of ions in the solution. Thus,

Λ_{m}

show a very

sharp increase for weak electrolytes