What is molarity of a solution of HCl which contains 49% by weight of solute and specific gravity is 1.41

Options

A. 15.25
B. 16.75
C. 18.92
D. 20.08

Answer

C

Explanation

Specific gravity refers to the ratio between density of a given substance and the density of a reference substance at the same temperature.
Specific gravity = `(rho_("substance"))/(rho_("water"))`
`therefore 1.41=(rho_(HCl))/(rho_("water"))`
1.41 = density of HCl
1.41 g / mL means 1.41 g in 1mL
`therefore` Moles of HCl is `(1.41)/(36.5)=("given mass")/("molar mass")`
and 49% means `(1.41)/(36.5)xx(49)/(100)xx1000=18.92`.