CAIE A Level Chemistry 9701 · States of matter
Silicon(IV) oxide, , has a very high melting point and is extremely hard. Iodine, , is a crystalline solid with a low melting point and is soft.
Compare the structure and bonding of silicon(IV) oxide and iodine, and use this to explain why silicon(IV) oxide has the higher melting point and is the harder solid.
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.
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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