Question

4 ml of pure A (d = 2.45 gm/ml) was added to 46 ml of B (d = `25.1/23` gm/ml), the molarity of a solution of A in B will be ______, if the density of the final solution is 1.8 gm/ml.

Given: Molar mass of A = 98, Molar mass of B = 46

Options

• 1

• 2

• 3

• 4

Answer 1

4 ml of pure A (d = 2.45 gm/ml) was added to 46 ml of B (d = `25.1/23` gm/ml), the molarity of a solution of A in B will be 3, if the density of the final solution is 1.8 gm/ml.

Explanation:

Mass of A = 2.45 × 4 = 9.8 gm

Mass of B = `46 × 25.1/23` = 50.2 gm

Total mass = 60 gm

Volume of solution = `60/1.8` ml

M_A = `(9.8//98)/(60//1.8) × 1000` = 3