Comparison of allotropic phosphorus modifications
November 13, 2020 | Education
| Comparison criteria | Phosphorus red | Phosphorus white |
Common signs | ||
1. Physical properties | Solid, crystalline substances | |
2. Belonging to a certain class of substances | Simple substances that are formed by the same element – phosphorus, that is, are its allotropic modifications | |
3. Chemical properties | Non-metals, interact with many simple substances (oxygen, halogens, sulfur, metals) and complex oxidizing substances (berthollet’s salt, nitric acid) | |
Signs of difference | ||
1. Structure | Has an atomic crystal lattice | Has a molecular crystal lattice and formula P4 |
2. Properties | The powder is red-brown in color, not poisonous. It does not dissolve in water or carbon disulfide. Does not glow in the dark. Lights up only when ignited | White waxy substance. Very poisonous.
It does not dissolve in water, but it dissolves well in carbon disulfide. Glows in the dark. Self-igniting in powder. Therefore, it is kept under water. |
Reactions with red phosphorus are less vigorous than with white phosphorus | ||
3. Receiving | Heating white phosphorus without air access for several hours at 375 – 400 ° С | By calcining a mixture of phosphorites, sand and coal:
2Са3 (РО4) 2 + 10С + 6SiО2 = 6CaSiО3 + Р4 + 10CO |
4. Application | For the production of matches and phosphate fertilizers | For the production of phosphoric acids, in military affairs (napalm, smoke bombs, self-igniting mixtures), for the production of pesticides |
