Question

Describe the preparation of white phosphorus.

Answer 1

1. Heat phosphate rock with silica and coke in an electric furnace at about 1770 K.
2. Phosphate rock contains calcium phosphate.
3. At high temperature, it reacts to form phosphorus vapour.
4. Phosphorus vapour is then condensed under water to get white phosphorus.
5. It is stored under water to prevent oxidation, as it ignites in air easily.