Limiting molar conductivity of ${\text{NH}}_4\text{OH}$ (${\Lambda }_m^0({\text{NH}}_4\text{OH})$) is equal to:

According to Kohlrausch's law, the limiting molar conductivity of an electrolyte can be represented as the sum of the individual contributions of the anion and cation.To get ${\text{NH}}_4\text{OH}$:${\Lambda }_m^0({\text{NH}}_4\text{OH})={\lambda }^0({\text{NH}}_4^{+})+{\lambda }^0({\text{OH}}^{-})$ We can achieve this by:$[{\lambda }^0({\text{NH}}_4^{+})+{\lambda }^0({\text{Cl}}^{-})]+[{\lambda }^0({\text{Na}}^{+})+{\lambda }^0({\text{OH}}^{-})]-[{\lambda }^0({\text{Na}}^{+})+{\lambda }^0({\text{Cl}}^{-})]$$⟹{\Lambda }_m^0({\text{NH}}_4\text{Cl})+{\Lambda }_m^0(\text{NaOH})-{\Lambda }_m^0(\text{NaCl})$.