DP Chemistry (first assessment 2025)
Question 19M.1A.HL.TZ2.25
| Date | May 2019 | Marks available | [Maximum mark: 1] | Reference code | 19M.1A.HL.TZ2.25 |
| Level | HL | Paper | 1A | Time zone | TZ2 |
| Command term | Question number | 25 | Adapted from | N/A |
25.
[Maximum mark: 1]
19M.1A.HL.TZ2.25
Which of the following can be both formed from bromoethane and converted directly into ethanal?
CH3CH2Br → X
X → CH3CHO
A. CH3CH2OH
B. CH3OCH3
C. CH3COOH
D. H2C=CHBr
[1]
Markscheme
A
Examiners report
The question involving a sequence of organic reactions discriminated well between high scoring and low scoring candidates. 68 % chose the correct compound.
Syllabus sections
Reactivity 3. What are the mechanisms of chemical change? » Reactivity 3.4—Electron-pair sharing reactions » Reactivity 3.4.2—In a nucleophilic substitution reaction, a nucleophile donates an electron pair to form a new bond, as another bond breaks producing a leaving group. Deduce equations with descriptions and explanations of the movement of electron pairs in nucleophilic substitution reactions.