3.3.7 Optical isomerism

Question 1

Optical isomerism definition

Answer 1

A type of stereoisomerism where two molecules have the same molecular formula and structural formula, but they are non-superimposable mirror images of each other.

Question 2

What is a chiral centre

Answer 2

Also known as an asymmetrical carbon. A carbon with 4 different groups attached

Question 3

Test for optical isomers

Answer 3

Shine plane polarised light at sample
Enantiomers will rotate light in opposite directions

Question 4

What is a racemic mixture

Answer 4

A mixture with equal amounts of each enantiomer

Question 5

Enantiomer definition

Answer 5

Optical isomers

Question 6

Why does a certain ketone/aldehyde/carboxylic acid produce a racemic mixture

Answer 6

Carbonyl bond is planar
With equal probability to attack from above and below
Giving equal amounts of enantiomers

Question 7

Explain why optical isomers cant both bind to the same enzyme

Answer 7

Enzyme has an active site
Only one optical isomer has correct stereochemistry / is stereospecific