Optical isomerism

how does optical isomerism occur

when there are four different substituents attached to one asymmetric chiral centred carbon atom

the two isomers are …

non-superimposable mirror images of one another

optical isomers differ in the way..

that they rotate the plane of polarisation of polarised light - clockwise (+) or anticlockwise(-)

two isomers can be called a pair of

enantiomers

the formula is represented by a

Star

the asymmetric carbon atom is referred to as the

chiral centre

all amino acids have a chiral centre except for

glycine

What does light consist of

vibrating electric and magnetic fields

what happens if light passes through a special filter called a polaroid?

all the vibrations are cut out except for those on one plane, so the light is vertically polarised

optical rotation can be measured by

a polarimeter

what does a polarimeter measure

rotation of the plane of polarisation of polarised light

describe method of using a polarimeter

• polarised light is passed through two solutions of the same concentration, each containing a different optical isomer of the same substance

• one solution will rotate the plane of polarisation clockwise (+), whilst another will rotate the plane of polarisation anticlockwise (-)