Pros and Cons of different separations techniques

Question 1

What are the cons of chromatography

Answer 1

That sample used cannot be used twice

Question 2

What are the pro’s of chromatography

Answer 2

Only a small amount of sample is needed

Question 3

What are the con’s of decanting

Answer 3

There are possibilities of the residue contaminating the filtrate(thus filtration is a preferred method as the filtrate that is collected is purer)

Question 4

What are the pro’s of evaporation to dryness

Answer 4

It is quick and easy

Question 5

What are the con’s of evaporation to dryness

Answer 5

• The solids obtained may not be very pure

- Small powdery solid obtained

Question 6

What are the pro’s of crystallisation

Answer 6

• the obtained substance is going to be purer

- able to get a larger quantity of substance

Question 7

what are the con’s of crystallisation

Answer 7

• a saturated solution has to be obtained

Question 8

what are the con’s of fractional distillation

Answer 8

A pure distillate would not be collected(aka not 100%)

• This is due to the very close boiling point (plus liquids evaporate at any temperature
• Though the fractionating column(for which is to increase surface area for repeated cycles of condensation) is there, there are still chances of the gas already escaping to the Liebig condenser, into the distillate