In one process, 5.95 kg of caf2 is treated with an excess of h2so4 and yields 2.45 kg of hf. calculate the percent yield of hf.

Answer is: yield of reaction is 80,3%.
Chemical reaction: CaF₂ + H₂SO₄ → CaSO₄ + 2HF.
m(CaF₂) = 5,95 kg · 1000 g/kg = 5950 g.
n(CaF₂) = m(CaF₂) ÷ M(CaF₂).
n(CaF₂) = 5950 g ÷ 78 g/mol.
n(CaF₂) = 76,28 mol.
From chemical reaction: n(CaF₂) : n(HF) = 1 : 2.
n(HF) = 76,28 mol · 2 = 152,56 mol.
m(HF) = 152,56 mol · 20 g/mol.
m(HF) = 3051,2 g ÷ 1000 g/kg = 3,0512 kg.
yield = 2,45 kg kg ÷ 3,0512 kg · 100% = 80,3%.