Question

Explain the method of separating iron filings, naphthalene and chalk powder.

Answer 1

The given mixture forms a homogeneous composition with 3 solid components.

Sublimation: The process of conversion of a solid substance directly into its vapours on heating and vapour into solid on cooling is called sublimation.

Magnetic separation: The process of separating the solid-solid mixture by using a magnet is called magnetic separation.

The following steps should be followed to separate a mixture containing chalk powder, iron filings, and naphthalene:

1. By moving the magnet over the mixture, iron filings are attracted by the magnet and separated.
2. Naphthalene and chalk powder is separated using sublimation.
3. It involves heating chalk powder and naphthalene together.
4. On heating, naphthalene sublimes, and its vapours condense over a cold apparatus.
5. Chalk powder, being nonvolatile, is left behind as residue.
6. Hence the 3 components are separated.