This question is about elements and compounds - AQA - GCSE Chemistry Combined Science - Question 7 - 2022 - Paper 1

The balanced equation for the reaction is:

$4 Na + TiCl₄ → 4 NaCl + Ti$

The half-equation showing the oxidation of sodium is:

$Na → Na^+ + e^-$

To determine the maximum mass of copper produced, we first need to find the limiting reactant:

1. Calculate the moles of aluminum: $n_{Al} = \frac{108 \text{ g}}{27 \text{ g/mol}} = 4 ext{ mol}$
2. Using the stoichiometry of the reaction, we find moles of Cu produced: From the equation, 2 moles of Al produce 3 moles of Cu. Therefore, 4 moles of Al will produce: $4 \text{ mol Al} \times \frac{3 \text{ mol Cu}}{2 \text{ mol Al}} = 6 \text{ mol Cu}$
3. Calculate maximum mass of Cu produced: $m_{Cu} = 6 \text{ mol} \times 63.5 \text{ g/mol} = 381 ext{ g}$ Hence, the maximum mass of copper produced is 381 grams.

Sodium metal conducts electricity by allowing delocalised electrons to carry an electric charge throughout the metal structure. These electrons can move freely, facilitating the flow of electric current.

Sodium chloride can conduct electricity when dissolved in water or when molten because it dissociates into ions. In solution, sodium ions (Na⁺) and chloride ions (Cl⁻) are free to move, enabling them to carry an electric charge. This ionic movement is essential for electrical conductivity.