Question

The density of a 2.03 M solution of acetic acid (molecular mass 60) in water is $1.017g/mL$. Calculate the molality of the solution.

Answer 1

Strength of the solution
$=Molarity\times mol.mass$
$=2.03\times 60=121.8g/L$
Density of solution $=1.017g/mL$
Mass of 1 litre of solution $=1000mL\times 1.017g/mL$
$=1017g$
Mass of water $=1017-121.8=895.2g=\frac{895.2}{1000}kg$
Molality $=\frac{2.03}{895.2}\times 1000=2.267m$