What will be the mass of carbon dioxide that will contain the same number of molecules as present in 3.2g of oxygen gas? [At. Wt: O=16, C=12]

Molecular mass of O₂ = 2 × 16 = 32 g/mol

Given mass = 3.2 g of Oxygen

Moles of O₂ = $\frac{\text{Mass}}{\text{Molar mass}}$ = $\frac{3.2}{32}$ = 0.1 mol

∴ 0.1 mol of O₂ contain = 0.1 x 6.023 × 10²³ of molecules.

We need the same number of molecules of CO₂

∴ Moles of CO₂ will also be 0.1 mol

Molar mass of CO₂ = 12 + 2(16) = 12 + 32 = 44 g/mol

Mass = moles x molar mass

Mass of CO₂ = 0.1 x 44 = 4.4 g.

∴ Mass of CO₂ = 4.4 g