Describe5 marksStandard
A pond freezes from the surface downwards because ice is less dense than liquid water. Describe the lattice structure of ice and show how this structure accounts for the lower density of ice compared with liquid water.
CAIE A Level Chemistry 9701 · States of matter
States of matter: describe question
How this question is marked
5 marks, so the mark scheme is looking for about 5 separate creditworthy points. Making the same point twice in different words earns it once.
Describe means: Say what happens or what something is like, in order and with detail. You are not being asked why. If there is data, quote it: name the trend, then give figures with units at the points where it changes.
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