Answer:
The chemist needs to react 40 g of sulfur with 60 g of oxygen to make 100 g of sulfur trioxide.
Step-by-step explanation:
2S (s) + 3O₂ (g) → 2SO₃ (g)
64g + 96g → 160 g
32g + 48g → 80 g
x + y → 100 g
1 mol SO₃ ___ 80g
n _______ 100g
n = 1.25 mol SO₃
1 mol S ___ 32 g
1,25 mol S __ 40 g
1 mol O₂ ___ 32 g
1,875 mol O₂ ___ 60 g