Chemistry 0620 · IGCSE · The mole and the Avogadro constant

The mole and the Avogadro constant — practice question

When calcium carbonate is heated, calcium oxide and carbon dioxide gas are produced. The reaction equation is given as: $\text{CaCO}_3 \rightarrow \text{CaO} + \text{CO}_2$. A mass of $225\,\text{kg}$ of calcium carbonate is heated until the mass stops changing. The mass of calcium oxide obtained is $85\,\text{kg}$. What is the percentage yield?

  • A37.8%
  • B47.2%
  • C67.5%
  • D85.0%

Worked solution & mark scheme

This 1-mark question has a full step-by-step worked solution and mark scheme.

  • Full mark scheme, point by point
  • Step-by-step worked solution
  • Write your answer & get it marked instantly by AI