Question

What is the amount of hydrogen fluoride you get from the action of 6.4g caf2 with excess sulfuric acid concentrated (h2so4)

Answer 1

Solution.

$CaF2 + H2SO4 = CaSO4 + 2HF$

$n(CaF2) = \frac{6.4}{78.07} = 0.082 \ mol$

$n(HF) = 2 \times n(CaF2) = 0.164 \ mol$

$m(HF) = 0.164 \times 20.00 = 3.28 \ g$

Answer:

m(HF) = 3.28 g