Q.

The molar conductivity of a weak electrolyte when plotted against the square root of its concentration, which of the following expected to be observed       [2025]

1 Molar conductivity decreases sharply with increase in concentration.  
2 A small increase in molar conductivity is observed at infinite dilution.  
3 A small decrease in molar conductivity is observed at infinite dilution.  
4 Molar conductivity increases sharply with increase in concentration.  

Ans.

(1)

With dilution, degree of dissociation of weak electrolyte increases hence number of charge carriers rise sharply and molar conductivity increases sharply.