DP Chemistry (last assessment 2024)
Question 19M.3.hl.TZ1.19a
| Date | May 2019 | Marks available | [Maximum mark: 2] | Reference code | 19M.3.hl.TZ1.19a |
| Level | hl | Paper | 3 | Time zone | TZ1 |
| Command term | Identify, Name | Question number | a | Adapted from | N/A |
a.
[Maximum mark: 2]
19M.3.hl.TZ1.19a
Aspirin can be obtained from salicylic acid.
(a)
Unreacted salicylic acid may be present as an impurity in aspirin and can be detected in the infrared (IR) spectrum.
Name the functional group and identify the absorption band that diff erentiates salicylic acid from aspirin. Use section 26 of the data booklet.
Name:
Absorption band:
[2]
Markscheme
Name:
hydroxyl [✔]
Absorption band:
3200–3600 «cm–1» [✔]
Note: Accept “phenol” OR “alcohol” but not “hydroxide”.
Examiners report
Many candidates scored a mark for naming a functional group that differentiates salicylic acid from aspirin. Some incorrectly said ether or carboxylic acid. Many candidates also scored for identifying the absorption band although 1700-1750 was a popular incorrect answer.
