Question

What is the unit of molality?

Answer 1

Molality: Molality of a solution is defined as the number of moles of solute dissolved in 1Kg of the solvent.

• Molality is represented by ‘m’.
• The formula for calculation of molality: $\mathrm{Molality}\left(\mathrm{m}\right)=\frac{\mathrm{moles}\mathrm{of}\mathrm{solute}}{\mathrm{mass}\mathrm{of}\mathrm{solvent}\left(\mathrm{Kg}\right)}$
• Therefore the unit of molality is$\frac{\mathrm{mol}}{\mathrm{Kg}}$ or ${\mathrm{molKg}}^{-1}$.
• Molality is an intensive property as both moles and mass are extensive, on dividing two extensive properties we get intensive property.