CAIE A Level Chemistry 9701 · The Periodic Table: chemical periodicity
The melting points of the elements sodium, magnesium, aluminium, silicon, phosphorus, sulfur, chlorine and argon vary across Period 3. Compare the melting points of these elements, and explain the variation in terms of the structure and bonding of the elements.
7 marks, so the mark scheme is looking for about 7 separate creditworthy points. Making the same point twice in different words earns it once.
Compare means: Give similarities or differences between two things, and say which side each point belongs to. Write each point as a pair, for example: A is X, whereas B is Y. Two separate descriptions rarely earn the marks.
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