Q40. Which out of the following is a correct equation to show change in molar conductivity with respect to concentration for a weak electrolyte, if the symbols carry their usual meaning :\\
(1) $\Lambda _ { \mathrm { m } } - \Lambda _ { \mathrm { m } } ^ { 0 } + \mathrm { AC } ^ { \frac { 1 } { 2 } } = 0$\\
(2) $\Lambda _ { m } ^ { 2 } \mathrm { C } - \mathrm { K } _ { \mathrm { a } } \Lambda _ { \mathrm { m } } ^ { \circ 2 } + \mathrm { K } _ { \mathrm { a } } \Lambda _ { \mathrm { m } } \Lambda _ { \mathrm { m } } = 0$\\
(3) $\Lambda ^ { 2 } { } _ { m } \mathrm { C } + \mathrm { K } _ { \mathrm { a } } \Lambda _ { \mathrm { m } } ^ { \circ 2 } - \mathrm { K } _ { \mathrm { a } } \Lambda _ { \mathrm { m } } \Lambda _ { \mathrm { m } } ^ { \circ } = 0$\\
(4) $\Lambda _ { \mathrm { m } } - \Lambda _ { \mathrm { m } } ^ { \circ } - \mathrm { AC } ^ { \frac { 1 } { 2 } } = 0$