CAIE A Level Chemistry 9701 · Chemical bonding
Compare the bonding in the ammonia molecule, , and the ammonium ion, , with reference to their dot-and-cross diagrams. In your answer, describe the number of bonding pairs and lone pairs on the central nitrogen atom in each species, and explain the nature of the bonds in the ammonium ion.
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.
Written by Markquill to follow the Cambridge International syllabus. Markquill is independent and is not affiliated with or endorsed by Cambridge International.