Sublimation is used to separate a mixture of Solid and a Solid
What is Sublimation?
It is a process where a solid directly converts into its gas phase without going into liquid state .
Example
- Solids like Ammonium chloride, Naphthalene,Camphor and Anthracene undergo Sublimation.
- When we heat them they convert directly into gases without first converting into liquid
Hence, to separate a mixture having a sublimable and non-sublimable component , we use the method of sublimation.
How to Separate a Mixture of Salt and Camphor?
In a mixture of Salt and Camphor,
Camphor
- Sublimes on heating
- Hence it is a sublimable component
Common salt (Sodium Chloride)
- Does not undergo sublimation
-
It is a
non sublimable component.
Procedure
- Take a mixture of salt and camphor in a china dish
- Place an inverted funnel over it
- Close the end of the funnel with a cotton plug
- Now heat the mixture
On heating , camphor undergoes sublimation (converts into vapours)
These vapors solidify again on the surface of the funnel
However salt does not undergo sublimation and remains on the china dish
