Answer:
(240 × 3 × 31.998)/(122.5 × 2) g
Step-by-step 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: 122.5 31.998
2KClO₃ ⟶ 2KCl + 3O₂
Mass/g: 240
Mass of O₂ = 240 g KClO₃ × (1 mol KClO₃/122.5 g KClO₃) × (3 mol O₂/2 mol KClO₃) × (31.998 g O₂/1 mol O₂) = 94.0 g O₂
Mass of O₂= (240 × 3 × 31.998)/(2 × 122.5) = 94.0 g O₂
True, all matter has mass and takes up space.
4 sig fig in that expression
