Question

The unit of molar conductivity is
(A) $Sc{m^2}{s^{ - 1}}$
(B) $S{l^2}mo{l^{ - 1}}$
(C) $S{m^2}mo{l^{ - 1}}$
(D) None of these

Answer 1

Conductivity term related to thermodynamics. In thermodynamics deals with the forms of heat and heat is the form of energy. And how one energy is converted into other forms of energy.

Complete step-by-step answer:
According to Ohm’s law voltage applied in a circuit is directly proportional to the current circulated in the circuit.
So $V \propto I \Rightarrow V = IR$
Here R is the resistance that slows up the speed of the current.
Conductance may be defined as it is the inverse to the resistance that fastens the speed of the current. It is denoted by $G$.
So $G \propto 1/R$
And the cell constant may be defined as the ratio of specific conductance of $KCl$ to the conductance of $KCl$.
Cell constant = specific conductance of $KCl$/conductance of $KCl$
For strong electrolyte, there is a small increase in molar conductivity because strong electrolyte completely dissociates into ions. For weak electrolyte there is a very large increase in conductivity because on dilution weak electrolyte dissociates into ions.
The unit of molar conductivity is $S{m^2}mo{l^{ - 1}}$ .

Hence option $C$ is the correct option.

Note: Two types of conductivity occur in electrochemistry-$(1)$ Molar conductivity- it is the conductivity occurs by total ions given by one mole of an electrolyte on V dilution when distance between two electrodes is $1cm$ and the area is so much that the whole solution is contained between them. This conductivity is known as molar conductivity.
$(2)$ Equivalent conductivity: it is the conductivity occurs by total ions given by one gram equivalent of an electrolyte on V dilution when distance between two electrodes is $1cm$ and the area is so much that the whole solution is contained between them. This conductivity is known as Equivalent conductivity.