Question

What mass of ammonium chloride is dissolved in 300 mL of a 0.875M solution?

Answer 1

Answer:

9.32 g.

Explanation:

• Molarity is the no. of moles of solute per 1.0 L of the solution.

M = (no. of moles of NH₄Cl)/(Volume of the solution (L))

M = 0.875 M.

no. of moles of NH₄Cl = ??? mol,

Volume of the solution = 300 mL = 0.3 L.

∴ (0.875 M) = (no. of moles of NH₄Cl)/(0.3 L)

∴ (no. of moles of NH₄Cl) = (0.875 M)*(0.3 L) = 0.2625 mol.

• To find the mass of NH₄Cl, we can use the relation:

no. of moles of NH₄Cl = mass/molar mass

∴ mass of NH₄Cl = (no. of moles of NH₄Cl)*(molar mass) = (0.2625 mol)*(53.491 g/mol) = 9.316 g ≅ 9.32 g.