When carbon is burned in air, it reacts with oxygen to form carbon dioxide. When 24.0 g of carbon were burned in the presence of 79.5 g of oxygen, 15.5 g of oxygen remained unreacted. What mass of carbon dioxide was produced
C + O2 ==> CO2
mass C used = 24 g
mass O used = 79.5 - 15.5 = 64 g
moles O2 = grams/molar mass = 64/32 = 2
2 mols O2 will produce 2 moles CO2 (from the equation)
mass CO2 produced = mols x molar mass = ?