DP Chemistry (first assessment 2025)
Question 19M.1A.HL.TZ1.37
| Date | May 2019 | Marks available | [Maximum mark: 1] | Reference code | 19M.1A.HL.TZ1.37 |
| Level | HL | Paper | 1A | Time zone | TZ1 |
| Command term | Question number | 37 | Adapted from | N/A |
37.
[Maximum mark: 1]
19M.1A.HL.TZ1.37
Which compound can exist as cis- and trans-isomers?
[1]
Markscheme
C
Examiners report
Cis and trans isomerism on cyclic alkanes was poorly answered. This had the lowest discriminatory index on the test and all incorrect answers were fairly evenly distributed.
Syllabus sections
Structure 3. Classification of matter » Structure 3.2—Functional groups: Classification of organic compounds » Structure 3.2.7—Stereoisomers have the same constitution (atom identities, connectivities and bond multiplicities) but different spatial arrangements of atoms. Describe and explain the features that give rise to cis-trans isomerism; recognize it in non-cyclic alkenes and C3 and C4 cycloalkanes. Draw stereochemical formulas showing the tetrahedral arrangement around a chiral carbon. Describe and explain a chiral carbon atom giving rise to stereoisomers with different optical properties. Recognize a pair of enantiomers as non-superimposable mirror images from 3D modelling (real or virtual).