Chirality

Question 1

Optical isomerism - Optical Isomers

Answer 1

Form of stereo-Isomers = optical isomers are Non-Superimposable images of each other/mirror images

Question 2

Stereo-Isomerism

Answer 2

Same atoms + groups but spatial structure means no matter how much you twist molecule they will never line up/be the same

Question 3

Chiral centres/carbons

Answer 3

Molecules with 4 different groups around 1 carbon atom = have 2 mirror images/optical isomers

Question 4

Why are optical isomers called optical

Answer 4

Rotate the plane of polarised light

Question 5

what property does light have

Answer 5

Polarisation = plane polarised light means all light has same polarisation

Question 6

Racemic mixture

Answer 6

Equimolar mixtures of 2 optical isomers
Not optically active as 2 optical isomers rotation cancel each other out exactly

Question 7

If a solution does not rotate plan of polarised light it means …

Answer 7

Racemic mixture of 2 optical isomers

Or No chiral centre

Question 8

Does SN1(Tertiary) produce optically active product and why

Answer 8

No - optically inactive
Formation of trigonal planar carbocation intermediate = Nucleophile can attack from 2 directions (above + below) = 2 possible isomers formed = Racemic mixture
Does not rotate plane of polarised light

Question 9

Does SN2 (Primary) produce optically active product and why

Answer 9

Yes - optically active
Nucleophile attacks opposite side to leaving grip = only 1 choice of attack
= one optical isomer formed = rotates plane of polarised light