Question

38% hcl by mass in water has density 1.2g/ml. Calculate its molarity

Answer 1

use the formula,

molarity = $\frac{p\times d\times 10}{M}$

where, p is the percentage of solute by mass,

d is the density of solution in g/ml

and M is the mass of solute in gram.

here, p = 38% by mass

d = 1.2g/ml

M = 1 + 35.5 = 36.5 [molar mass of HCl ]

so, molarity = 38 × 1.2 × 10/36.5 = 12.49mol/L

hence, molarity of solution is 12.49 mol/L