Calculate the percent by mass of potassium nitrate in a solution made from 45.0 g kno3 and 295 ml of water. the density of water is 0.997 g/ml.

 the percent by mass of potassium nitrate is 13.3%

Explanation:

1) Data:

Mass of solute, m₁ = 45.0 gVolume of solvent, V₂ = 295 mldensity of water, d₂ = 0.997 g/ml

2) Formulae:

Percent by mass, % = (mass of solute / mass of solution) × 100Density, d = mass / volume

3) Solution:

d = mass / volume ⇒ m₂ = d₂ × V₂ = 0.997 g/ml × 295 ml = 294. gmass of solution = m₁ + m₂ = 45.0g + 294. g = 339. g% = (45.0 g / 339. g) × 100 = 13.3 %The answer has to be reported with 3 significant figures.

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