SiO2 + 4 HF --> SiF4 + 2 H2O Given 15.0 mol HF, how many moles of H2O will be produced? If the same 15.0 mol HF reacts how many grams of SiF4 will be produced?

Answer 1

SiO₂ + 4HF --> SiF₄ + 2H₂O ... balanced equation

This is just like the other problems you have posted. You simply use the stoichiometry from the balanced equation and dimensional analysis to find the mass of H₂O and/or SiF₄ produced.

For grams H₂O produced:

15.0 mol HF x 2 mol H₂O/4 mol HF x 18.0 g H₂O/mol H₂O = 135 g H2O produced (3 sig. figs.)

For SiF₄ produced:

15.0 mol HF x 1 mol SiF₄/4 mol HF x 104 g SiF₄/mol SiF₄ = 390 g SiF₄ produced (3 sig. figs.)