The density of 3 molal solution of NaOH is 1.110 g mL-1. Calculate the molarity of the solution.

3 molal solution of NaOH means 3 moles of NaOH are dissolved in 1 kg solvent. So, the mass of solution = 1000 g solvent + 120 g NaOH = 1120 g solution
(Molar mass of NaOH=23+16+1=40g and 3 moles of NaOH=3×40=120g)
Volumeofsolution=MassofsolutionDensityofsolution
V=1120g1.110gmL-1=1009mL
Molarity=Molesofsolute×1000Volumeofsolution(mL)
=3×10001009=2.973M3M