DP Chemistry (last assessment 2024)
Question 19M.3.hl.TZ2.9c
| Date | May 2019 | Marks available | [Maximum mark: 2] | Reference code | 19M.3.hl.TZ2.9c |
| Level | hl | Paper | 3 | Time zone | TZ2 |
| Command term | State and explain | Question number | c | Adapted from | N/A |
c.
[Maximum mark: 2]
19M.3.hl.TZ2.9c
Proteins have structural or enzyme functions.
(c)
State and explain how a competitive inhibitor affects the maximum rate, Vmax, of an enzyme-catalyzed reaction.
[2]
Markscheme
Vmax unchanged [✔]
at high substrate concentration substrate outcompetes inhibitor/need a higher
substrate concentration to reach Vmax [✔]
Note: Accept suitable labelled diagram.
Examiners report
Many candidates stated correctly that Vmax remains unchanged but only some mentioned that a higher substrate concentration was required to reach Vmax for the second mark.
