Chapter 2

Question 1

Stereochemistry

What is an isomer?

Answer 1

The study of the arrangement of atoms - in a molecule - in three dimensions

Isomers - 2 different molecules with the same number and type of atoms (same formula) are called isomers.

Question 2

2x different isomers?

Answer 2

1) Structural isomers - con-structural isomers.
- Different by their connectivity (The order and kinds of bonds)

2)Stereoisomers - Spacial Isomers - Differ in the way the atoms are arranged in space.

Question 3

Functional Isomers

Answer 3

Structural isomers that have the same molecular formula but different functional groups.

Question 4

Positional or Regio isomers

Answer 4

Structural isomers where the functional group moves position on the parent structure.

Question 5

Geometric Isomers

Answer 5

Occur because carbon bonds that are in a ring or double bond - unable to freely rotate

In general structural and geometric isomers have different reactivity, spectra and physical properties.

Question 6

Cis/Trans Configuration

Answer 6

When the subunits are on the same side of the ring or double bond it is cis

On oposit side it is trans. Trans are more stable.

Question 7

Steriocentre

Answer 7

An atom bearing attachments.

Such that interchanging only two groups produces a stereoisomer

Question 8

Chirality

Answer 8

Chiral molecules contain at least one molecule.

Chiral carbon

A carbon atom with four different substituents attached

Question 9

Enantiomers/Diasteomers

2x types of stereoisomers

Answer 9

Enantiomers - come in pairs - 2 non super imposable molecules which are mirror images of each other. Must be chiral

Diastereomers are any pair of stereoisomers that are not enantiomers.
Are both chemically and physically different from each other.