Question 22M.2.hl.TZ1.5b(ii)
| Date | May 2022 | Marks available | [Maximum mark: 2] | Reference code | 22M.2.hl.TZ1.5b(ii) |
| Level | hl | Paper | 2 | Time zone | TZ1 |
| Command term | Explain | Question number | b(ii) | Adapted from | N/A |
Organomagnesium compounds can react with carbonyl compounds. One overall equation is:
Compound B can also be prepared by reacting an alkene with water.
Explain why the reaction produces more (CH3)3COH than (CH3)2CHCH2OH.
[2]
carbocation formed from (CH3)3COH is more stable / (CH3)3C+ is more stable than (CH3)2CHCH2+ ✔
«because carbocation has» greater number of alkyl groups/lower charge on the atom/higher e- density
OR
«greater number of alkyl groups» are more electron releasing
OR
«greater number of alkyl groups creates» greater inductive/+I effect ✔
Do not award any marks for simply quoting Markovnikov’s rule.
Poor performance, particularly in light of past feedback provided in similar questions since there was repeated reference simply to Markovnikov's rule, without any explanation.
