IGCSEScienceCambridge (CIE)Combined ScienceChemistryExam Questions3. StoichiometryFormulae & Equations

Formulae & Equations (Cambridge (CIE) IGCSE Combined Science: Chemistry): Exam Questions

Exam code: 0653

4 mins3 questions
1
1 mark

Which equation for the reaction between magnesium and dilute hydrochloric acid is correct?

  • Mg (s) + 2HCl (l) → MgCl2 (l) + H2 (g)

  • Mg (s) + 2HCl (aq) → MgCl2 (aq) + H2 (g)

  • 2Mg (s) + 2HCl (l) → 2MgCl2 (l) + H2 (g)

  • 2Mg (s) + 2HCl (aq) → 2MgCl2 (aq) + H2 (g)

Choose your answer

2
1 mark

The formula of sodium phosphate is Na₃PO₄.

The formula of calcium chloride is CaCl₂.

What is the formula of calcium phosphate?

  • CaPO4

  • Ca3(PO4)2

  • Ca(PO4)2

  • Ca3PO4

Choose your answer

3
2 marks

Gasoline contains octane, C8H18. Octane is a liquid at room temperature.

Complete the state symbols to show the states of octane, carbon dioxide, carbon monoxide and carbon particulates at room temperature:

C8H18(...............) CO2(..............) CO(.............) C(...............)

How did you do?