Date | November 2019 | Marks available | 2 | Reference code | 19N.3.sl.TZ0.17 |
Level | SL | Paper | 3 | Time zone | TZ0 |
Command term | Outline | Question number | 17 | Adapted from | N/A |
Question
The structure of aspirin is shown in section 37 of the data booklet.
Suggest one reactant used to prepare aspirin from salicylic acid.
Aspirin, C6H4(OCOCH3)COOH, is only slightly soluble in water.
Outline, including an equation, how aspirin can be made more water-soluble. Use section 37 in the data booklet.
Markscheme
NOTE: Accept condensed structural formulas.
Accept “ethanoic acid/acetic acid/CH3COOH”.
Accept “C4H6O3” OR “C2H3OCl”.
react with sodium hydroxide/NaOH/«strong» base
OR
convert to «ionic» salt ✔
NOTE: Accept other suitable bases (eg, KOH/NaHCO3/Na2CO3) with corresponding equation for chosen base for M2.
Accept “CaCO3”, although calcium salicylate is not water soluble.
Accept ionic equation.
C6H4(OCOCH3)COOH (s) + NaOH (aq) → C6H4(OCOCH3)COONa (aq) + H2O (l) ✔
NOTE: Award [2] for M2.