Answer:
5.25 g NaF
Explanation:
We know we will need a balanced equation with masses and molar masses, so let’s gather all the information in one place.
M_r: 41.99
Na₂SiO₃ + 8HF ⟶ H₂SiF₆ + 2 NaF + 3H₂O
n/mol: 8
(1) Calculate the moles of NaF
The molar ratio is 2 mol NaF/8 mol HF.
Moles of F = 0.500 mol HF × (2 mol Na₂SiO₃/8 mol HF)
Moles of Na₂SiO₃ = 0.125 mol Na₂SiO₃
(2) Calculate the mass of NaF
Mass of NaF = 0.125 mol NaF × (41.99 g Na₂SiO₃/1 mol Na₂SiO₃)
Mass of NaF = 5.25 g NaF