Find the molarity and molality of a 15% solution of H2SO4 ( density=1 020 g/cm3 and atomic mass = H=1, - Chemistry - Some Basic Concepts of Chemistry

Question

Find the molarity and molality of a 15% solution of H2SO4 (
density=1 020 g/cm3 and atomic mass = H=1, O=16, S=32amu)

Kanika Dalal · Accepted Answer

Dear Student,

Molarity can be calculated as:

$M = \frac{(% m a s s) x 10 x d}{M M}$

where %mass = 15 %

d = 1.020 g/cm³

MM = 98 g/mol

$M = \frac{15 x 10 x 1.020}{98} M = 1.56 M$

Now, Molality can be calculated with the help of Molarity, using the following formula:

$m = \frac{1000 x M}{(1000 x d) - (M x M M)}$

where, M= molarity = 1.56 M

d = density = 1.020 g/cm³

MM = Molar mass of solute = 98 g/mol

$m = \frac{1000 x 1.56}{(1000 x 1.020) - (1.56 x 98)} m = \frac{1560}{867.12} m = 1.80 m o l / k g$

Hope, its clear now.

Enjoy learning!!

Find the molarity and molality of a 15% solution of H2SO4 ( density=1.020 g/cm3 and atomic mass = H=1, O=16, S=32amu)