Phosphorus (symbol P, atomic number 15) is a reactive nonmetal vital to DNA, ATP, and bone, and a key fertiliser nutrient. It is classified as a reactive nonmetal and sits in group 15, period 3 of the periodic table.
Overview
Phosphorus is the chemical element with atomic number 15 and the symbol P. With a standard atomic weight of 30.974, it is a reactive nonmetal. In the periodic table it occupies group 15 and period 3, and under standard conditions it is normally a solid. Phosphorus is a reactive nonmetal vital to DNA, ATP, and bone, and a key fertiliser nutrient.
Atomic structure
An atom of Phosphorus has 15 protons in its nucleus and, when neutral, 15 electrons arranged in the configuration [Ne] 3s2 3p3. Its standard atomic weight of 30.974 reflects the natural mix of its stable isotopes.
Discovery and place in the table
Phosphorus was discovered in 1669 by Hennig Brand. It follows Silicon (Si) and precedes Sulfur (S) in order of atomic number.
| Atomic number | 15 |
|---|---|
| Symbol | P |
| Atomic mass | 30.974 |
| Category | Reactive nonmetal |
| Group | 15 |
| Period | 3 |
| Electron configuration | [Ne] 3s2 3p3 |
| Phase at STP | Solid |
| Discovered | 1669 (Hennig Brand) |