There are four allotropes of phosphorus: red phosphorus, white phosphorus, purple phosphorus and black phosphorus. ?
Properties of phosphorus:
White phosphorus will transform into red phosphorus when heated to 250°C or exposed to light without air. Red phosphorus is non-toxic and does not catch fire until it is heated above 400°C. Under high pressure, white phosphorus can transform into black phosphorus, which has a layered network structure and can conduct electricity. It is the most stable allotrope of phosphorus.
Element description:
Elemental phosphorus has several allotropes. Among them, white phosphorus or yellow phosphorus is a colorless or light yellow transparent crystalline solid. Density 1.82 g/cm3. The melting point is 44.1℃, the boiling point is 280℃, and the ignition point is 40℃. It emits phosphorescence when placed in a dark place. There is a stench. Highly toxic.
White phosphorus is almost insoluble in water and easily soluble in carbon disulfide solvent. When heated under high pressure, it turns into black phosphorus, which has a density of 2.70 g/cm3 and is slightly metallic. The ionization energy is 10.486 electron volts. Insoluble in common solvents.
White phosphorus can be converted into red phosphorus by being placed or heated in an airtight manner at 400°C for several hours. Red phosphorus is a reddish-brown powder, non-toxic, with a density of 2.34 g/cm3, a melting point of 59°C, a boiling point of 200°C, and an ignition point of 240°C. Insoluble in water.
Expand knowledge:
Phosphorus is the 15th chemical element with the symbol P. It is in the third period of the periodic table of elements and group VA. Phosphorus exists in all cells of the human body. It is an essential substance for maintaining bones and teeth, and participates in almost all physiological chemical reactions. Phosphorus is also an important substance that makes the heart beat regularly, maintains normal kidney function, and transmits nerve stimulation.
Without phosphorus, niacin (also known as vitamin B3) cannot be absorbed; the normal function of phosphorus requires vitamin D (vitamin food) and calcium to maintain. The discovery of phosphorus has to start with alchemy in the European Middle Ages. At that time, alchemy was popular. It was said that as long as you found a wise man's stone, the philosopher's stone, you could turn the stone into gold and turn ordinary lead and iron into precious gold.
The alchemist is like a madman, using strange utensils and substances, chanting incantations in his mouth in a dark cabin, refining in the fire, stirring in a vat, thinking about it day and night. The philosopher's stone that turns stone into gold.