It, therefore, becomes
necessary to define a physically more meaningful quantity called molar
conductivity denoted by the symbol Lm (Greek, lambda) It is related
to the conductivity of the solution by the equation:
Molar conductivity = Lm = c

(2 21)
In the above equation, if k is expressed in S m–1 and the concentration,
c in mol m–3 then the units of Lm are in S m2 mol–1 It may be noted that:
1 mol m–3 = 1000(L/m3) × molarity (mol/L), and hence
Lm(S cm2 mol–1) = 




1
3
1
 (S cm
)
1000 L m
 × molarity (mol L )
If we use S cm–1 as the units for k and mol cm–3, the units of
concentration, then the units for Lm are S cm2 mol–1