The correct expression and unit of molar conductivity ($Λ_m$) are:

$Λ_m= κV; ohm^{-1}\,cm^{2}\,mol\, L^{-1}$

The correct answer is Option (3) → $Λ_m= κV; ohm^{-1}\,cm^{2}\,mol\, L^{-1}$

Molar conductivity is given by the formula:

$\Lambda_m = \kappa \times V$

where

• $κ$ = conductivity
• V = volume containing 1 mole of electrolyte (in cm³)

The unit of molar conductivity is:

$\text{ohm}^{-1}\,\text{cm}^2\,\text{mol}^{-1}$

✅ Correct answer: $Λ_m= κV; ohm^{-1}\,cm^{2}\,mol\, L^{-1}$