Chirality

Question 1

Chiral def

Answer 1

Non-superimposable on its mirror image.

Question 2

What is optical activity

Answer 2

Rotation of plane of polarised light

Question 3

Racemic mixture

Answer 3

50:50 mixture of two enantiomers. Optically inactive because two enantiomers rotate plane of polarised light equally in opposite directions.

Question 4

Optical activity of SN1 reaction

Answer 4

If initially pure optical isomer, equal chance of attack from above or below the plane of the trigonal planer carbocation, racemic mixture formed.

Question 5

Optical activity of SN2 reaction

Answer 5

If initially pure optical isomer, stereochemistry is inversed, pure product optical isomer, optically active mixture formed.