Question

Calculate the mass percentage of solvent in an aqueous solution prepared by dissolving 11.9 g KMnO4 in 198. g H2O. The molar mass of KMnO4 is 158.03 g/mol and the molar mass of H2O is 18.02 g/mol.

Answer Bank

63.8% by mass

5.67% by mass

91.5% by mass

94.3% by mass

8.50% by mass

Answer 1

Answer:

The mass percentage of the solvent is 94.3% by mass.

Explanation:

We prepare a solution dissolving 11.9 g KMnO₄(solute) in 198g H₂O(solvent). The mass of the solution is:

mass of solution = mass of solute + mass of solvent

mass of solution = 11.9g + 198g = 210g

The mass percentage of the solvent is:

$\% H_{2}O = \frac{massH_{2}O}{massofsolution} \times 100\% = \frac{198g}{210g} \times 100\% = 94.3\%$