| Date | May 2009 | Marks available | 1 | Reference code | 09M.1.hl.TZ2.39 |
| Level | HL | Paper | 1 | Time zone | TZ2 |
| Command term | Identify | Question number | 39 | Adapted from | N/A |
Question
Which statement is correct about the enantiomers of a chiral compound?
A. Their physical properties are different.
B. All their chemical reactions are identical.
C. A racemic mixture will rotate the plane of polarized light.
D. They will rotate the plane of polarized light in opposite directions.
Markscheme
D
Examiners report
One respondent stated that there were two answers to this question (A and D). The only correct answer is D, namely that, the enantiomers of a chiral compound rotate the plane of polarized light in opposite directions. Enantiomers have the same physical properties. However, diastereomers which are stereoisomers that are not enantiomers can have different physical properties.
