CAIE A Level Chemistry 9701 · Chemical energetics
Consider the following changes:
(a) The dissolution of ammonium nitrate in water:
(b) The decomposition of ammonia:
For each change, predict the sign of the entropy change () and explain your reasoning in terms of the number of possible arrangements of the particles and their energy.
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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