Question

What symbol is used to denote ‘molality’?

(a) M

(b) m

(c) mM

(d) n

This question was posed to me in quiz.

This question is from Expressing Concentration of Solutions topic in chapter Solutions of Chemistry – Class 12

Answer 1

Correct option is (b) m

Easiest explanation: Universally, ‘m’ is used to denote molality concentrations. E.g. 2 m means a solution having concentration 2 molal (2 moles of solute/kg solvent). ‘M’ is used to molarity. E.g. 2 M means a solution having concentration 2 molar (2 moles of solute/L solution). ‘mM’ corresponds to milli-molar concentration and ‘n’ denotes number of moles of a component.