Practice Questions

Gas volumes follow mole ratios. Ratio N₂:H₂ = 1:3. Therefore 5 dm³ nitrogen requires 15 dm³ hydrogen.

Molecular formula is C₆H₁₂O₆ because 180/30 = 6. Thus each mole contains 12 moles hydrogen atoms.

Twelve moles of water react with one mole Al₄C₃. Mass = 12 × 18 = 216 g.

16 g CH₄ = 1 mol. One mole methane requires two moles oxygen. Mass = 2 × 32 = 64 g.

Benzene contains six carbon atoms in each molecule, so one mole contains six moles of carbon atoms.

The balanced equation shows equal coefficients for K and KOH, giving a simplified ratio of 1:1.

10 g CaCO₃ = 0.1 mol. One mole CaCO₃ gives one mole CO₂. Therefore volume = 0.1 × 22.4 = 2.24 dm³.

Urea contains two nitrogen atoms per molecule. Thus 0.5 mol nitrogen atoms correspond to 0.25 mol urea. Mass = 0.25 × 60 = 15 g.

From the ratio, 2 mol H₂S produce 3 mol S. Therefore, 1 mol H₂S produces 1.5 mol S. Mass = 1.5 × 32 = 48 g.

One mole of CCl₄ contains 4 moles of Cl atoms. Thus 0.5 mol contains 2 mol Cl atoms.