The density of 3M solution of NaCL is 1.25 g`mL^(-1)`. Calculate molality of the solution.

Explanation

Molarity of NaCl `=3 mol L^(-1)`
Mass of NaCl in 1L solution `=3 xx 58.5=175.5g`
Mass of 1 L solution `=d xx v =1.25 xx 1000=1250g`
=1074.5g -1.0745 kg
Molality `=("No. of moles of solute")/("Mass of solvent in kg")`
`=(3)/(1.0745)=2.79m`