Titration Mathematics: Past Paper Questions
Topic 3.3.4 | Quantitative Chemistry | Cambridge IGCSE Chemistry 0620
Essential Formulae
Moles = Concentration (mol/dm³) × Volume (dm³)
Concentration = Moles / Volume (dm³)
⚠️ Always convert cm³ to dm³: divide by 1000
Section A: Apparatus & Method
Which piece of apparatus is used to measure a variable volume of liquid accurately during a titration?
Which piece of apparatus is used to measure a fixed volume of 25.0 cm³ of solution accurately?
What is the purpose of an indicator in an acid-base titration?
In a titration, what color change indicates the end-point when using methyl orange indicator with acid in the flask?
Why should the conical flask be rinsed with water, not with the solution being titrated?
Section B: 1:1 Calculations (Simple Neutralization)
25.0 cm³ of 0.100 mol/dm³ hydrochloric acid reacts exactly with 20.0 cm³ of sodium hydroxide solution. Calculate the concentration of the sodium hydroxide in mol/dm³. HCl(aq) + NaOH(aq) → NaCl(aq) + H₂O(l)
20.0 cm³ of 0.150 mol/dm³ nitric acid reacts exactly with 25.0 cm³ of potassium hydroxide solution. Calculate the concentration of the potassium hydroxide in mol/dm³. HNO₃(aq) + KOH(aq) → KNO₃(aq) + H₂O(l)
25.0 cm³ of 0.200 mol/dm³ sodium hydroxide reacts exactly with 30.0 cm³ of hydrochloric acid. Calculate the concentration of the hydrochloric acid in mol/dm³. NaOH(aq) + HCl(aq) → NaCl(aq) + H₂O(l)
15.0 cm³ of 0.100 mol/dm³ ethanoic acid reacts exactly with 22.5 cm³ of sodium hydroxide solution. Calculate the concentration of the sodium hydroxide in mol/dm³. CH₃COOH(aq) + NaOH(aq) → CH₃COONa(aq) + H₂O(l)
25.0 cm³ of 0.080 mol/dm³ hydrochloric acid reacts exactly with 16.0 cm³ of potassium hydroxide solution. Calculate the concentration of the potassium hydroxide in mol/dm³. HCl(aq) + KOH(aq) → KCl(aq) + H₂O(l)
Section C: 1:2 Calculations (Dibasic Acids)
25.0 cm³ of 0.100 mol/dm³ sulfuric acid reacts exactly with 25.0 cm³ of sodium hydroxide solution. Calculate the concentration of the sodium hydroxide in mol/dm³. H₂SO₄(aq) + 2NaOH(aq) → Na₂SO₄(aq) + 2H₂O(l)
20.0 cm³ of 0.150 mol/dm³ sulfuric acid reacts exactly with 30.0 cm³ of potassium hydroxide solution. Calculate the concentration of the potassium hydroxide in mol/dm³. H₂SO₄(aq) + 2KOH(aq) → K₂SO₄(aq) + 2H₂O(l)
25.0 cm³ of 0.200 mol/dm³ sodium hydroxide reacts exactly with 12.5 cm³ of sulfuric acid. Calculate the concentration of the sulfuric acid in mol/dm³. 2NaOH(aq) + H₂SO₄(aq) → Na₂SO₄(aq) + 2H₂O(l)
25.0 cm³ of 0.120 mol/dm³ sulfuric acid reacts exactly with 40.0 cm³ of sodium hydroxide solution. Calculate the concentration of the sodium hydroxide in mol/dm³. H₂SO₄(aq) + 2NaOH(aq) → Na₂SO₄(aq) + 2H₂O(l)
30.0 cm³ of 0.100 mol/dm³ potassium hydroxide reacts exactly with 10.0 cm³ of sulfuric acid. Calculate the concentration of the sulfuric acid in mol/dm³. 2KOH(aq) + H₂SO₄(aq) → K₂SO₄(aq) + 2H₂O(l)
⚠️ EXAMINER TRAPS - Avoid These Common Mistakes!
- 1.Volume Units: ALWAYS convert cm³ to dm³ (divide by 1000). Writing concentration with cm³ instead of dm³ = 0 marks!
- 2.Mole Ratios: H₂SO₄ is dibasic (1:2 ratio with NaOH). Forgetting to multiply/divide by 2 is the most common error in Section C!
- 3.Significant Figures: Give answers to 2 or 3 s.f. unless told otherwise. "0.166666..." gets 0 marks; "0.167 mol/dm³" gets full marks.
- 4.Working: ALWAYS show your working. Even if your final answer is wrong, you can still earn method marks!
- 5.Units: Final answer MUST include units (mol/dm³). No units = automatic mark deduction!
📊 Mark Scheme Keywords (Paper 4)
For Apparatus Questions:
- • Burette = variable volume accurately
- • Pipette = fixed volume accurately
- • Indicator = shows end-point
For Calculation Questions:
- • Always write: Moles = conc × vol
- • Show mole ratio from balanced equation
- • Include units in final answer
Cambridge IGCSE Chemistry 0620 (2026-2028) | Topic 3.3.4: Titration Calculations
These questions follow the style and difficulty of actual Paper 4 past papers
Sign In to Keep Going
You've reached the end of the free preview. Sign in — and upgrade to Plus or Pro — to keep going with Chemistry.
Full Access
Unlock all 320 lessons