Molality (m) of 3 M aqueous solution of NaCl is: (Given: Density of solution =1.25 g mL^-1, Molar mass in g mol^-1: Na -23, Cl -35.5 )

Molality (m) of $\displaystyle 3$ M aqueous solution of NaCl is : (Given : Density of solution $\displaystyle =1.25 \mathrm{~g} \mathrm{~mL}^{-1}$, Molar mass in $\displaystyle \mathrm{g} \mathrm{mol}^{-1}: \mathrm{Na}-23, \mathrm{Cl}-35.5$ )