DP Chemistry (last assessment 2024)
Question 18M.3.hl.TZ2.27b
| Date | May 2018 | Marks available | [Maximum mark: 3] | Reference code | 18M.3.hl.TZ2.27b |
| Level | hl | Paper | 3 | Time zone | TZ2 |
| Command term | Predict | Question number | b | Adapted from | N/A |
b.
[Maximum mark: 3]
18M.3.hl.TZ2.27b
Ethanol can be detected by a variety of instruments.
(b)
Predict the chemical shifts and integration for each signal in the 1H NMR spectrum for ethanol using section 27 of the data booklet.
[3]
Markscheme
R–OH:
1.0–6.0 «ppm» AND 1 H
R–O–CH2–:
3.3–3.7 «ppm» AND 2 H
–CH3:
0.9–1.0 «ppm» AND 3 H
Award [1] for the ratio of 1:2:3 (in any order).
Award [2] for three correct chemical shifts without integration.
Award [1] for two correct chemical shifts without integration.
For each chemical shift accept a specific value within the range.
Assignment of proton to fragment (eg, R–OH) is not required in each case.
[3 marks]
