Practice Questions

3.011 × 10²³ molecules = 0.5 mole. Volume = 0.5 × 22.4 = 11.2 dm³.

108 g Al = 4 moles. The ratio 4Al : 2Al₂O₃ gives 2 moles Al₂O₃.

50 g CaCO₃ = 0.5 mole. It forms 0.5 mole CaO. Mass = 0.5 × 56 = 28 g.

44.8 dm³ = 2 moles NH₃. Each molecule has 4 atoms. Total atoms = 8 moles of atoms = 4.8176 × 10²⁴ atoms.

30 g of C₂H₆ = 1 mole. One mole of C₂H₆ produces 3 moles of H₂O. Mass of water = 3 × 18 = 54 g.

Molar mass = (4.4 × 10⁻²² g) × (6.022 × 10²³ mol⁻¹) ≈ 265 g/mol.

The volume ratio SO₂ : SO₃ is 1:1. Hence, 44.8 dm³ of SO₂ produces 44.8 dm³ of SO₃.

Each AlCl₃ gives 4 ions. Therefore, 0.5 × 4 = 2 moles of ions. Number of ions = 2 × 6.022 × 10²³ = 1.2044 × 10²⁴.

Moles = 1 ÷ 22.4 = 0.0446 mol. Molar mass = 1.25 ÷ 0.0446 ≈ 28 g/mol.

Moles of N₂ = 28 ÷ 28 = 1 mole. One mole of N₂ forms 2 moles of NH₃. Volume = 2 × 22.4 = 44.8 dm³.