Chemistry 9701 · AS & A Level · Atoms, molecules and stoichiometry

Atoms, molecules and stoichiometry — practice question

Hydrogen peroxide, $\text{H}_2\text{O}_2$, breaks down into water and oxygen when an appropriate catalyst is introduced. $20.0\,\text{cm}^3$ of aqueous hydrogen peroxide decomposes and gives $600\,\text{cm}^3$ of oxygen under room conditions. What is the concentration of the aqueous hydrogen peroxide?

  • A$5.00\,\text{mol dm}^{-3}$
  • B$2.50\,\text{mol dm}^{-3}$
  • C$1.25\,\text{mol dm}^{-3}$
  • D$0.625\,\text{mol dm}^{-3}$

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