Question

Molar ionic conductivities of a bi-bivalent electrolyte are 57 and 73. The molar conductivity of the solution will be :

• A. $130Sc{m}^{2}mo{l}^{-1}$
• B. $65Sc{m}^{2}mo{l}^{-1}$
• C. $260Sc{m}^{2}mo{l}^{-1}$
• D. $187Sc{m}^{2}mo{l}^{-1}$

Answer 1

The correct option is A $130Sc{m}^{2}mo{l}^{-1}$

According to kohlrausch law of independent migration of ions, the molar conductivity of an electrolyte

at infinite dilution is equal to the sum of the contributions of the molar conductivities of its ions.
Hence,
${\Lambda }_{AB}={\lambda }_{A2+}+{\lambda }_{B2-}=57+73=130S{cm}^2{mol}^{-1}.$

Hence, option A is correct.