Question 1
The graph shows a titration curve recorded with a pH meter as 0.100 mol L⁻¹ sodium hydroxide is added to a 25.00 mL aliquot of an acid. What does the curve show?
How to answer WACE Chemistry short answer and extended answer questions
Calculations need every step, significant figures and a unit; written answers follow the command word: describe gives features, explain adds cause and effect, and evaluate ends with a judgement.
| Short answer | 8 to 12 questions: equations, descriptions, short calculations, diagrams |
|---|---|
| Extended answer | 5 to 7 questions in parts, each on a scenario or experimental data |
| Calculations | 15 to 20% of the examination, with working shown |
Write to the question
- For a calculation, write each step with its formula, carry the units and give the answer to sensible significant figures.
- For an equation, balance atoms and charge and give state symbols; half-equations are written for acidic conditions.
- For explain, give the point, tie it to the substance, conditions or data in the question, then say what it causes.
Use the scenario
Quote the numbers, the substances or the observation in the question. An answer that could be written without reading the scenario is rarely a full-marks answer.
Try 2 questions
Question 2
Four standard reduction potentials are Ag⁺/Ag +0.80 V, Cu²⁺/Cu +0.34 V, Fe²⁺/Fe −0.44 V and Zn²⁺/Zn −0.76 V. Which species is the strongest oxidising agent?
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Questions people ask
How long should an extended answer be?
Long enough to make each point, tie it to the scenario and develop it. Plan two or three linked points rather than a list.