Question

Calculate the boiling point of a 1M aqueous solution (density 1.04 g mL-1 ) of Potassium chloride (Kb for water = 0.52 K kg mol-1 , Atomic masses: K=39u, Cl=39.9u) Assume, Potassium chloride is completely dissociated in solution

Answer 1

we know relation molality , molarity and density
1/m=d/M-Msolute/1000
=1.04-78.9/1000=1.04-0.0789=0.9611
m =1/0.9611
now use the concept of elevation of boiling point=Kbxm
=0.52x1/0.9611
so, elevation in boiling point=5200/9611
boiling point=5200/9611+initial boiling point