DP Chemistry (last assessment 2024)
Question 20N.2.sl.TZ0.4a
Date | November 2020 | Marks available | [Maximum mark: 1] | Reference code | 20N.2.sl.TZ0.4a |
Level | sl | Paper | 2 | Time zone | TZ0 |
Command term | Outline | Question number | a | Adapted from | N/A |
a.
[Maximum mark: 1]
20N.2.sl.TZ0.4a
Nickel catalyses the conversion of propanone to propan-2-ol.
(a)
Outline how a catalyst increases the rate of reaction.
[1]
Markscheme
provides an alternative pathway/mechanism AND lower ✔
Accept description of how catalyst lowers (e.g. “reactants adsorb on surface «of catalyst»”, “reactant bonds weaken «when adsorbed»”).
Examiners report
A straight-forward question, however, half of the candidates only mentioned the lower activation energy and did not mention that this is through an alternative mechanism, so did not score the mark.
