Question

Which of the following concentration terms temperature independent ?
(I) Molarity (II) Molality
(III) Normality (IV) Mole fraction

• A. I & II
• B. I & III
• C. II only
• D. II and IV

Answer 1

The correct option is D II and IV

Molarity is given by $M=\frac{n_{solute}}{V_{solution}}$ here $V$ is the volume of the solution which is temperature dependent.

Molality is given by $m=\frac{n_{solute}}{W_{solvent}}$ $W_{solvent}$ is the mass of solvent which is independent of temperature.

Normality is given by $N=\frac{n_{\text{equivalent solute}}}{V_{solution}}$

Here, it is dependent on volume which is temperature dependent.

Mole fraction is dependent on the amount of substance which is temperature independent.

Therefore, Molality and mole fraction are temperature independent.