Phosphorous

Phosphorus is a chemical element with atomic number 15 and the symbol P. Phosphorus exists in two primary forms: white phosphorus and red phosphorus, however it is never found as a free element on Earth due to its extreme reactivity. It has a concentration of roughly one gram per kilogram in the Earth’s crust (compare copper at about 0.06 grams). Phosphate is the most common form of phosphorus in minerals.
White phosphorus was the first element to be separated in 1669.
When white phosphorus is exposed to oxygen, it creates a weak glow, hence the name, which comes from Greek mythology and refers to the “Morning Star,” the planet Venus.

Physical properties 

Phosphorus (P) is a colourless, semitransparent, soft, waxy solid that glows in the dark. It is a non-metallic chemical element of the nitrogen family.

Phosphorus on the periodic table

It is a highly reactive waxy non-metal with the symbol P. In the periodic table’s group 15, the pnictogens, it’s to the left of sulphur, to the right of silicon, and below nitrogen. The electron configuration of the phosphorus atom is [Ne]3s23p3 or 1s22s22p63s23p3.

Phosphorus Allotropes

White Phosphorus- White phosphorus is the element’s most poisonous allotrope.White phosphorus becomes spontaneously combustible when exposed to air, and contact with the skin produces severe burns.
Four phosphorus atoms form a closed ring shape in white phosphorus molecules thanks to covalent bonding. The low bond angle created by this shape causes strain within the molecule, which explains its high reactivity.
White phosphorus is exceedingly hazardous and can result in serious injury or death.

Red phosphorus is a less hazardous allotrope than its counterpart. It looks like a powdered red-iron material with a beautiful sheen. White phosphorus is less stable and harmful than red phosphorus. Small amounts can be removed from striker strips found on match boxes.
When white phosphorus rings polymerize via covalent connections to create straight chains, red phosphorus is formed. These chains reduce the molecule’s reactivity by lowering intramolecular strain.

Black Phosphorus: Unlike red phosphorus, black phosphorus is less reactive.
It looks like a crystalline solid that is black and glossy.
The relative stability of this structure is aided by the higher bond angle that results from this shape. Black phosphorus has no reactivity toward sulphur, oxygen, or halogens because it is a less reactive allotrope.The former, which is more stable, is achieved by heating red phosphorus. After heating white phosphorus under pressure, the latter, which is more reactive, is synthesised.

Violet Phosphorus: Violet phosphorus is a virtually all-black crystalline solid with a faint purple tint.It’s the least reactive allotrope, taking a long time to react with halogens.
Heat red phosphorus in a sealed tube or dissolve white phosphorus in molten lead to make violet phosphorus.

Reactions

Oxygen + Phosphorus

This element easily combusts when exposed to oxygen, producing thick white vapours.

P4O10 →  P4(s) + 5O2(g)

Halogens + Phosphorus

P4(s) + 6F2(g) →  4PF3 Fluorine (g)

4PCl3 →   P4(s) + 6Cl2(g) + P4(s) + 6Cl2(g) (l)

P4(s) + 6Br2(g)  →  4PBr3 Bromine (l)

P4(s) + 6I2(g)  →  4PI3 Iodine (g)

Water + Phosphorus

Scientists commonly store phosphorus underwater to avoid interactions with air since it does not react with water.

PH3(g) + H3PO3 →  2P4(s) + 3H2O(l) (s)

Acids + Phosphorus

When phosphorus interacts with HCl, phosphine and phosphorus(III) chloride are formed.

P4(s) + 6HCl(l) →  2PH3(g) + 2PCl3

Phosphorus Compounds

Phosphorus is nearly totally employed in the form of compounds, with the +5 oxidation state being the most common.
Calcium phosphate (Ca3(PO4)2), apatite (Ca5(PO4)3OH), fluorapatite (Ca5(PO4)3F), and chlorapatite (Ca5(PO4)3Cl) are some of the most common phosphate compounds. The most common phosphate fertiliser is calcium dihydrogen phosphate, sometimes known as superphosphate: Ca(H2PO4)2.
The very poisonous chemical hydrogen phosphine: PH3 is used as a catalyst in several organic phosphorus synthesis processes.
Phosphorus pentoxide (P4O10) is a dehydrating and condensing agent that occurs when white phosphorus is burnt. It forms phosphoric acid when it combines aggressively with water. The oxidation state of phosphorus is +5. P4O6 is a tetra-phosphorus hexoxide that acts as a phosphorous anhydride. This chemical contains phosphorus in the +3 oxidation state.
Phosphorus pentoxide is treated with water to produce orthophosphoric acid, H3PO4, which has industrial use. H3PO3 is a phosphorus acid that serves as an intermediary in the production of other phosphorus compounds.

Phosphorus Trichloride

Dry chlorine is passed over heated white phosphorus to produce phosphorus trichloride.

4PCl3 → P4 + 6Cl2.

It’s also made when thionyl chloride reacts with white phosphorus.

4PCl3 + 4SO2 + 2S2Cl2 →  P4 + 8SOCl2

It is a colourless, oily liquid that hydrolyzes when exposed to moisture.

Oxidation States of Phosphorus

+5 is the most frequent oxidation number. In phosphites and phosphides, oxidation states of +3 and -3 are also seen. Phosphides are formed when metals react with red phosphorus. The +3 state of phosphorus is also present in phosphine.
Phosphorus Isolation: Scientists generally extract elemental phosphorus using calcium phosphate derived from phosphate rock in the following procedure. At 1500 degrees Celsius, this reaction takes place. Aluminum can also be utilised, allowing the reaction to occur at a lower temperature.

Conclusion

Phosphorus is necessary for steel manufacture. Phosphates are used in some detergents, however in other countries they are being phased out. This is because they can produce excessive phosphate levels in natural water supplies, which can contribute to the growth of undesired algae. Phosphates are also employed in the manufacture of exquisite chinaware and unique glassware.
Fertilizers are by far the most common usage of phosphorus compounds. Phosphate ores are used to make ammonium phosphate. Before being turned into ammonium phosphate, the ores must first be transformed into phosphoric acids.