CAIE A Level Chemistry 9701 · Reaction kinetics
A gaseous reaction occurs between reactants A and B:
Describe, in terms of the frequency of effective collisions, how the rate of this reaction is affected by each of the following changes.
(i) An increase in the concentration of A at constant temperature and volume.
(ii) An increase in the total pressure of the system at constant temperature, achieved by reducing the volume.
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.
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.