optical isomerism

Question 1

what type of isomerism is optical isomerism

Answer 1

stereoisomerism

same molecular
different spacial arrangement

Question 2

when does optical isomerism occur

Answer 2

asymmetrical carbon

chiral centre

4 different groups

Question 3

optical isomers

Answer 3

non-superimposable

mirror images

enantiomers

optically active

Question 4

chiral centres

Answer 4

marked with asterisk

Question 5

rotating light

Answer 5

both enantiomers rotate light opposite ways by the same amount

Question 6

clockwise

Answer 6

dextroratotory

Question 7

anti clockwise

Answer 7

laevoratatory

Question 8

plane polarised light

Answer 8

only vibrates in one direction

normal light vibrates in all directions

Question 9

racemate

Answer 9

racemic mixture

equal amounts of each enantiomer

don’t show optical activity

when 2 chiral molecules react, a racemate is formed as there is an equal chance of each enantiomer being formed

Question 10

nucleophilic addition

Answer 10

nucleophile can attack molecule with carbonyl group from above or below C=O bond

Question 11

formation of a racemate

Answer 11

optical isomers produce pair of enantiomers in 1:1 ratio

Question 12

drugs

Answer 12

easier to synthesise racemate

separating gives enantiopure compound

expensive

half may be effective, half may be harmful

waste of materials for 50% effective drug