Chemistry 0620 · IGCSE · The mole and the Avogadro constant

The mole and the Avogadro constant — practice question

Gas syringe X holds $100\text{ cm}^3$ of hydrogen bromide gas, $\text{HBr}$. Gas syringe Y holds $100\text{ cm}^3$ of carbon dioxide gas. Each gas volume is measured at room temperature and pressure. Which statement is correct?

  • AThe mass of HBr is less than the mass of $\text{CO}_2$.
  • BThe number of molecules of HBr equals the number of molecules of $\text{CO}_2$.
  • CThe gas in syringe X contains more atoms than the gas in syringe Y.
  • DThe number of moles of HBr is more than the number of moles of $\text{CO}_2$.

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