Classification of Matter A.2 Classification of Organic Compounds (id: 3c54e95a9)

本题目来源于试卷: Classification of Matter A.2 Classification of Organic Compounds，类别为 IB化学

[单选题]
The structural formulae+ h5xt;dw.nm or.mzlq )44daq ptfoaw, r -p(- ownimk,t 2sp/tj,tl 6m(( wei,f three compounds are shown.

A student measures the optical activities of the three compounds using a polarimeter. Which of the following results are they most likely to obtain?

A. Activity of 1 / degrees is 3.0 ; Activity of 2 / degrees is 5.0 ; Activity of 3 / degrees is 3.2
B. Activity of 1 / degrees is 3.0 ; Activity of 2 / degrees is -5.0 ; Activity of 3 / degrees is 0.0
C. Activity of 1 / degrees is 5.0 ; Activity of 2 / degrees is 5.0 ; Activity of 3 / degrees is 3.2
D. Activity of 1 / degrees is 5.0 ; Activity of 2 / degrees is -5.0 ; Activity of 3 / degrees is 0.0


参考答案:  D


本题详细解析:
Explanation:

1 and 2 are enantiomers, exhibiting opposite optical activities (rotate plane polarised light in opposite directions by the same amount).
Compound 3 is achiral, so it has a rotation angle of 0 degrees.
This question is in the “hard” category, as the student must be able to determine a molecule's chirality and recall how polarimetry can be used to distinguish between stereoisomers.

微信扫一扫，分享更方便