DP Chemistry (last assessment 2024)
Question 17N.3.sl.TZ0.20a
| Date | November 2017 | Marks available | [Maximum mark: 2] | Reference code | 17N.3.sl.TZ0.20a |
| Level | sl | Paper | 3 | Time zone | TZ0 |
| Command term | Explain | Question number | a | Adapted from | N/A |
a.
[Maximum mark: 2]
17N.3.sl.TZ0.20a
Excess acid in the stomach can cause discomfort and more serious health issues.
(a)
Explain how ranitidine (Zantac) reduces stomach acid production.
[2]
Markscheme
blocks/binds to H2/histamine receptors «in cells of stomach lining»
OR
prevents histamine binding to H2/histamine receptors «and triggering acid secretion»
prevents parietal cells from releasing/producing acid
Accept "H2-receptor antagonist/H2RA" OR "blocks/inhibits action of histamine" for M1.
