Isomers

Question 1

Isomers are molecules with the

Answer 1

Same molecular formula but difference in structure

Question 2

Stereoisomers differ in how

Answer 2

Atoms are oriented

Question 3

Horizontal wedges in Fischer projections display atoms going

Answer 3

Out of the plane / page

Question 4

Vertical wedges in Fischer projections display atoms going

Answer 4

In the plane / page

Question 5

The amount of rotation by polar polarized light depends on the

Answer 5

Number of molecules a light wave encounters

Question 6

The number of possible stereoisomers is given by equation

Answer 6

2^n

Question 7

The equation for specific rotation is

Answer 7

Observed retention / Concentration • Length

Question 8

Epimers are

Answer 8

Diastereomers that differ by 1 C

Question 9

Conformational isomers differ by

Answer 9

Rotation

Question 10

Conformational isomers differ in

Answer 10

Rotation around sigma bonds

Question 11

Configurational isomers can be interconverted by

Answer 11

Breaking bonds

Question 12

Ring strain can be caused by:

Answer 12

• Angle strain
• Torsional strain
• Steric strain

Question 13

Angle strain results when

Answer 13

Bond angles deviate from their ideal values by being

stretched or compressed.

Question 14

Torsional strain results when cyclic molecules must

Answer 14

Assume conformations that have eclipsed or gauche interactions

Question 15

Chair confirmation is one such type that

Answer 15

Eliminates all three strains that cause overall ring strain

Question 16

The two categories of configurational isomers are

Answer 16

• Enantiomers

- Diastereomers

Question 17

Achiral objects have

Answer 17

Mirror images that can be superimposed

Question 18

Two molecules that are nonsuperimposable mirror images of each other are called

Answer 18

Enantiomers

Question 19

Enantiomers have identical physical and chemical properties with two notable exceptions:

Answer 19

• Optical activity

- Reactions in chiral environments

Question 20

Enantiomers have nearly identical physical properties and chemical properties, but they

Answer 20

Rotate plane-polarized light in opposite directions

Question 21

Diastereomers are

Answer 21

Non-mirror-image configurational isomers

Question 22

Diastereomers are required to have

Answer 22

Multiple chiral centerd

Question 23

Possible stereocenters can be determined by the equation

Answer 23

2^n

Question 24

Cis–trans isomers are a type of

Answer 24

Diastereomers

Question 25

For a molecule to have optical activity, it must have

Answer 25

- Chiral centers | - Lack a plane of symmetry

Question 26

A molecule with chiral centers that has an internal plane of symmetry is called a

Answer 26

Meso compound

Question 27

The configuration of a stereoisomer refers to the

Answer 27

Spatial arrangement of the atoms or groups in the molecule.

Question 28

The relative configuration of a chiral molecule is its configuration in relation to

Answer 28

Another chiral molecule

Question 29

The absolute conformation of a chiral molecule describes the

Answer 29

Exact spatial arrangement of these atoms or groups, independent of other molecules

Question 30

Two atomic orbitals may combine to form:

Answer 30

- Bonding molecular orbital - Antibonding molecular orbital - Hybridized orbitals

Question 31

Molecular orbitals can contain a maximum of

Answer 31

Two orbitals

Question 32

A π bond is weaker than a single bond because there is

Answer 32

Less overlap between the unhybridized p-orbitals of a π bond than between the s-orbitals or hybrid orbitals of a σ bond.

Question 33

Why is a single bond stronger than a π bond?

Answer 33

S-orbitals have more overlap than p-orbitals.

Question 34

A resonance structure describes

Answer 34

A potential arrangement of electrons in a molecule

Question 35

Compared to single bonds, triple bonds are

Answer 35

More rigid