Explain4 marksStandard
A student adds an excess of solid magnesium hydroxide to dilute sulfuric acid and warms the mixture. State what is observed and write an equation for the reaction. Explain why the reaction occurs.
CAIE A Level Chemistry 9701 · Group 2
Group 2: explain question
How this question is marked
4 marks, so the mark scheme is looking for about 4 separate creditworthy points. Making the same point twice in different words earns it once.
Explain means: Give the reasons or the mechanism: why or how something happens. Link each point to the next with because, so or which means. A list of facts with no links usually loses the reasoning marks.
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