Answer is: 100.72 grams of calcium fluoride.
Balanced chemical reactions:
1) CaF₂ + H₂SO₄ → 2HF + CaSO₄.
2) 2HF → F₂ + H₂.
1) From chemical reaction 2: n(F₂) : n(HF) = 1 : 2.
n(HF) = 2 · 1.29 mol.
n(HF) = 2.58 mol.
2) From chemical reaction 1: n(HF) : n(CaF₂) = 2 : 1.
n(CaF₂) = 2.58 mol ÷ 2.
n(CaF₂) = 1.29 mol; amount of substance.
m(CaF₂) = n(CaF₂) · M(CaF₂).
m(CaF₂) = 1.29 mol · 78.08 g/mol.
m(CaF₂) = 100.72 g.
