CAIE A Level Chemistry 9701 · Halogen compounds
Ethane gas is mixed with chlorine and the mixture is exposed to ultraviolet light. A reaction takes place in which one of the hydrogen atoms of ethane is replaced by a chlorine atom.
Describe the reagents and conditions needed for this reaction, and name and outline the mechanism by which it occurs.
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.
Written by Markquill to follow the Cambridge International syllabus. Markquill is independent and is not affiliated with or endorsed by Cambridge International.