Practice Questions

Every molecule contains four chlorine atoms. Therefore, 0.5 mole CCl₄ contains 2 moles of chlorine atoms.

Multiplying the mass of one atom by Avogadro's number gives approximately 16 g mol⁻¹.

4.6 g Na equals 0.2 mole. According to the equation, 2 moles Na produce 1 mole H₂. Thus, 0.2 mole Na produces 0.1 mole H₂.

One formula unit produces five ions. Therefore, 0.1 mole gives 0.5 mole of ions, equal to 3.011 × 10²³ ions.

Nineteen grams correspond to 0.25 mole CS₂. This produces 0.5 mole SO₂ having a mass of 32 g.

Avogadro's law relates gas volume directly with the number of molecules at constant temperature and pressure.

The balanced equation is 3Fe + 4H₂O → Fe₃O₄ + 4H₂. Their sum is 12.

Percentage yield = (0.45 ÷ 0.75) × 100 = 60%.

Number of moles is inversely proportional to molar mass.

The atomic mass of helium is four grams per mole.