DP Chemistry (last assessment 2024)
Question 19M.3.hl.TZ2.b(ii)
| Date | May 2019 | Marks available | [Maximum mark: 1] | Reference code | 19M.3.hl.TZ2.b(ii) |
| Level | hl | Paper | 3 | Time zone | TZ2 |
| Command term | Determine | Question number | b(ii) | Adapted from | N/A |
b(ii).
[Maximum mark: 1]
19M.3.hl.TZ2.b(ii)
A student synthesized aspirin, acetylsalicylic acid, in a school laboratory.
0.300 g of crude aspirin was dissolved in ethanol and titrated with sodium hydroxide solution, NaOH (aq).
NaOH (aq) + C9H8O4 (in ethanol) → NaC9H7O4 (aq) + H2O (l)
Determine the percentage purity of the synthesized aspirin.
[1]
Markscheme
« × 100 % »= 97.7 «%» [✔]
Examiners report
A significant number of candidates were able to calculate the percentage purity of aspirin correctly although some managed an ECF mark.
