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patriot [66]
3 years ago
15

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.
Chemistry
1 answer:
Tanzania [10]3 years ago
6 0

Answer:  the percent by mass of potassium nitrate is 13.3%

Explanation:

<u>1) Data:</u>

  • Mass of solute, m₁ = 45.0 g
  • Volume of solvent, V₂ = 295 ml
  • density of water, d₂ = 0.997 g/ml

<u>2) Formulae</u>:

  • Percent by mass, % = (mass of solute / mass of solution) × 100

  • Density, d = mass / volume

<u>3) Solution</u>:

  • d = mass / volume ⇒ m₂ = d₂ × V₂ = 0.997 g/ml × 295 ml = 294. g
  • mass 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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