Answer to Question #174461 in Chemistry for amman

Question

Ammonium phosphate NH43PO4 is an important ingredient in many fertilizers. It can be made by reacting phosphoric acid H3PO4 with ammonia NH3. What mass of ammonium phosphate is produced by the reaction of 10.g of ammonia? Be sure your answer has the correct number of significant digits.

Answer 1

Solution:

The balanced chemical equation:

3NH₃ + H₃PO₄ → (NH₄)₃PO₄

According to the equation above: n(NH₃)/3 = n((NH₄)₃PO₄)

Moles of NH₃ = Mass of NH₃ / Molar mass of NH₃

The molar mass of NH₃ is 17.031 g mol^-1.

Hence,

Moles of NH₃ = 10.0 g / 17.031 g mol^-1 = 0.5872 mol

n((NH₄)₃PO₄) = n(NH₃)/3 = 0.5872 mol / 3 = 0.1957 mol

Mass of (NH₄)₃PO₄ = Moles of (NH₄)₃PO₄ × Molar mass of (NH₄)₃PO₄

The molar mass of (NH₄)₃PO₄ is 149.087 g mol^-1.

Hence,

Mass of (NH₄)₃PO₄ = 0.1957 mol × 149.087 g mol^-1 = 29.18 g = 29. g

Mass of (NH₄)₃PO₄ = 29 g

OR (short form solution):

(10. g NH₃) × (1 mol NH₃ / 17.031 g NH₃) × (1 mol (NH₄)₃PO₄ / 3 mol NH₃) × (149.087 g (NH₄)₃PO₄ / 1 mol (NH₄)₃PO₄) = 29.18 g (NH₄)₃PO₄ = 29. g (NH₄)₃PO₄

Answer: 29. g of ammonium phosphate is produced.