Sublimation

We all have seen camphor.

Camphor is mainly used in worship for lightning the lamp and it is also used for several medicinal purposes.

We have noticed after burning, the camphor is directly converted into the gas.

Whereas normally, after getting a heat, solid first converted into the liquid and after that, it is converted into the gas.

Whereas, in this case, the camphor, that is solid and is directly converted into the gas after getting heat.

This direct conversion of solid into the gas is called sublimation process.

Let's discuss the sublimation.

The direct conversion of a solid into the gas without melting in the liquid is called sublimation process.

And the substance which directly converted into the gas from the solid is called sublimable substance.

For examples, Camphor, naphthalene balls, ammonium chloride, dry ice, etc.

The sublimation process is used to separate the mixture having a sublimable substance and non-sublimable substance.

Suppose we have a mixture of ammonium chloride ($N{H}_{4}Cl$) and common salt (Sodium chloride, NaCl).

And we want to separate it into the single component.

Here, the ammonium chloride is the sublimable volatile substance. Volatile means, it is converted into the gas within a second after getting a heat.

And the sodium chloride is the non-sublimable substance as well as non-volatile.

Hence, we can simply separate it by the sublimation process.

For that, we have a burner over which a china disc is kept with the help of tripod stand.

And in the china disc, we keep the mixture that is covered with an inverted funnel.

Funnel another end is blocked by a cotton plug.

Now, we switch ON the burner.

After getting heat, ammonium chloride starts converted into the vapour.

Since, the funnel end is blocked, the vapour of ammonium chloride will be stuck on the side of the funnel and gets condensed/solidified.

And the sodium chloride will be left on the bottom of the funnel.

Hence, we have separated out the mixture into the components.

This is all about the sublimation process.

Revision

The direct conversion of a solid into the gas without melting in the liquid is called sublimation process.

Camphor, naphthalene balls, ammonium chloride, dry ice, etc. are examples of sublimable substances.

When we heat up a mixture of ammonium chloride and salt, the ammonium chloride will be vaporized.

Because, ammonium chloride is a sublimable volatile component.

And it will be stuck on the side of the funnel.

The End