Question 1

Which of the following best describes the difference between chiral and achiral objects, as illustrated by the comparison of hands and flasks?

Accepted Answer

Chiral objects cannot be superimposed on their mirror images, while achiral objects can.

Question 2

Which of the following molecules is achiral based on the provided images and study materials?

Accepted Answer

A flask, as shown in the first image.

Question 3

Which statement about enantiomers is correct based on the second image and the study materials?

Accepted Answer

Enantiomers are non-superimposable mirror images.

Question 4

According to the Cahn-Ingold-Prelog rules, how do you assign R or S configuration to a chiral center?

Accepted Answer

Assign priorities to the four groups, orient the lowest priority group away, and trace from 1 to 2 to 3; clockwise is R, counterclockwise is S.

Question 5

Which of the following statements about diastereomers is true?

Accepted Answer

Diastereomers are stereoisomers that are not mirror images.

Question 6

A molecule with two chiral centers can have a maximum of how many stereoisomers?

Accepted Answer

$4$

Question 7

Which of the following is true about the physical properties of enantiomers?

Accepted Answer

Enantiomers have identical physical properties except for their interaction with plane-polarized light and other chiral molecules.

Question 8

A racemic mixture is best described as:

Accepted Answer

A 50:50 mixture of two enantiomers, which is optically inactive.

Question 9

Which of the following compounds is a meso compound?

Accepted Answer

cis-1,2-dimethylcyclobutane

Question 10

Which of the following statements about optical activity is correct?

Accepted Answer

A racemic mixture is optically inactive because the rotations of the enantiomers cancel each other.

Question 11

Given the structure in the third image, how many chirality centers does the molecule have?

Accepted Answer

$1$

Question 12

Which of the following best explains why (R)-carvone and (S)-carvone smell different?

Accepted Answer

They interact differently with chiral olfactory receptors in the nose.

Question 13

If a molecule has an internal plane of symmetry in any of its conformations, it is:

Accepted Answer

Achiral

Question 14

Which of the following is NOT a requirement for a carbon atom to be a chirality center?

Accepted Answer

It must be part of a ring.

Question 15

Which of the following statements about Fischer projections is correct?

Accepted Answer

Vertical lines represent bonds going away from the viewer.

Question 16

Which of the following best describes a diastereomer of (3S, 5S)-3,5-dimethylheptan-4-one?

Accepted Answer

A molecule with only one center inverted, such as (3S, 5R)

Question 17

Which of the following is true about the relationship between specific rotation and absolute configuration?

Accepted Answer

Specific rotation can distinguish enantiomers but not assign R or S.

Question 18

Which of the following statements is correct regarding the 2n rule for stereoisomers?

Accepted Answer

A molecule with n chiral centers can have up to $2^n$ stereoisomers, but may have fewer due to meso compounds.

Question 19

Which of the following is a correct statement about conformational isomers?

Accepted Answer

They can be optically active only at high temperature.

Question 20

A 50:50 mixture of two enantiomers will be:

Accepted Answer

Optically inactive

Stereoisomers and Chirality: Study Notes for Organic Chemistry

Study Guide - Practice Questions