How conductance varies with concentration of weak electrolytes?

Increase in conductance at lower concentration 

The conductance of weak electrolytes varies with concentration in the following manner: 1. Increase in conductance at lower concentration.

For weak electrolytes, the degree of ionization (or dissociation) into ions is relatively low at lower concentrations. As the concentration of the weak electrolyte decreases, the number of ions in the solution becomes proportionally smaller. However, the mobility of these ions remains relatively constant.

The conductance of an electrolyte is directly proportional to the number of ions present in the solution and their mobility. At lower concentrations, even though the number of ions is smaller, the mobility of these ions is relatively high because the solvent's effect on the ion-ion interactions is reduced.

Therefore, the conductance of weak electrolytes tends to increase as the concentration decreases and vice versa. Hence, the correct answer is option 1: Increase in conductance at a lower concentration.