(a) Solutions of two electrolytes 'A' and 'B' are diluted. The limiting molar conductivity of 'B' increases 1.5 times while that of 'A' increases 25 times. Which of the two is a strong electrolyte ? Justify your answer.
(b) The products of electrolysis of aqueous NaCl at the respective electrodes are :
Cathode : `H_(2)`, Anode : `Cl_(2)` and not `O_(2)`. Explain.

Explanation

(a) 'B' is a strong elctrolyte sinece it is already almost completely ionised (`alpha~~1`). Dilution simply helps in its dissociation i.e., the ions get separated. Therefore, the increase in molar conductivity upon dilution is small. However, 'A' is a weak electrolyte because it is weakly ionised `alpha lt 1)`. Dilution helps in its ionisation as well as dissociation. Therefore, the increase in molar conductivity is quite large. For more details, consult section 19.
(b) For explanation, consult section 15.