Chemistry 0620 · IGCSE · Acid–base titrations

Acid–base titrations — practice question

(a)[3]

Determine the concentration of the dilute sulfuric acid by finding: the moles of aqueous potassium hydroxide used; the moles of dilute sulfuric acid needed to neutralise the aqueous potassium hydroxide; the concentration of the dilute sulfuric acid.

(b)[5]

Describe the method you would use to obtain a pure, dry sample of potassium sulfate crystals from fresh solutions of dilute sulfuric acid and aqueous potassium hydroxide with the same concentrations as those used in the titration. Include the main stages in your response.

(c)[4]

Describe what you would observe when these experiments are carried out: magnesium ribbon is added to an excess of solution X; a flame test is performed on solution X; an aqueous solution containing barium ions is added to solution X.

(d)[6]

Write the chemical equations for the reactions of dilute sulfuric acid with each of the following: magnesium hydroxide; zinc; sodium carbonate.

Worked solution & mark scheme

This 18-mark question has a full step-by-step worked solution and mark scheme. One marking point: moles of KOH come to 0.00125 mol (1.25 \times 10⁻^{3})

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