Question

A 5 molar solution is 27.75% CaCl2 by mass, what is the density of the solution?

(a) 1 g/cm^3

(b) 2 g/cm^3

(c) 3 g/cm^3

(d) 4 g/cm^3

I have been asked this question in an international level competition.

I'd like to ask this question from Concentration topic in chapter Moles, Density & Concentration of Basic Chemical Engineering

Answer 1

Correct option is (b) 2 g/cm^3

The explanation is: Let the mass of Solution be 100 grams, => moles of CaCl2 = 27.75/111 = 0.25, Density of solution = 5*(100/0.25) = 2000 kg/m^3 = 2 g/cm^3.