DP Chemistry (first assessment 2025)
Question 20N.1A.SL.TZ0.36
| Date | November 2020 | Marks available | [Maximum mark: 1] | Reference code | 20N.1A.SL.TZ0.36 |
| Level | SL | Paper | 1A | Time zone | TZ0 |
| Command term | Deduce | Question number | 36 | Adapted from | N/A |
36.
[Maximum mark: 1]
20N.1A.SL.TZ0.36
What will be the major product in the reaction between but-1-ene and ?
A. 2-bromobut-1-ene
B. 1-bromobut-1-ene
C. 2-bromobutane
D. 1-bromobutane
[1]
Markscheme
C
Examiners report
The vast majority selected the correct product for the reaction of but-1-ene and HBr although quite a few selected the minor product of 1-bromobutane.
Syllabus sections
Reactivity 3. What are the mechanisms of chemical change? » Reactivity 3.4—Electron-pair sharing reactions » Reactivity 3.4.5—Alkenes are susceptible to electrophilic attack because of the high electron density of the carbon–carbon double bond. These reactions lead to electrophilic addition. Deduce equations for the reactions of alkenes with water, halogens, and hydrogen halides.