Question

Determine the mass of oxygen necessary to react with 2.3 moles of HCl

Answer 1

4HCl + O₂ → 2Cl₂ + 2H₂O

mole ratio of HCl : O₂ is 4 : 1

∴ if moles of HCl = 2.3 mol

then mol of O₂ = 2.3 mol ÷ 4
= 0.575 mol

mass of O₂ = moles of O₂ × molar mass of O₂
= 0.575 mol × (16 × 2) g/mol
= 18.4 g