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Phosphorus [P] – Element Details, History, Atomic Structure, Facts, Properties, Electronic Configuration, Atomic Spectrum, Uses.

Phosphorus Symbol


Phosphorus is 15th element of Periodic table with atomic number 15, atomic weight 30.973761. Phosphorus, symbol ‘P’, has a Simple Triclinic structure and Colorless color. Phosphorus is a other nonmetal element. Trivial name of Phosphorus is pentels, pnictogens*. Know everything about Phosphorus Facts, Physical Properties, Chemical Properties, Electronic configuration, Atomic and Crystal Structure.


History of Phosphorus

The element Phosphorus was discovered by Hennig Brand in year 1669 in Germany . Phosphorus derived its name from the Greek word phoosphoros, ‘carrying light’

Phosphorus is a chemical element with symbol P and atomic number 15. As an element, phosphorus exists in two major forms—white phosphorus and red phosphorus—but due to its high reactivity, phosphorus is never found as a free element on Earth. Instead phosphorus-containing minerals are almost always present in their maximally oxidised state, as inorganic phosphate rocks.

How to Locate Phosphorus on Periodic Table

Periodic table is arranged by atomic number, number of protons in the nucleus which is same as number of electrons. The atomic number increases from left to right. Periodic table starts at top left ( Atomic number 1) and ends at bottom right (atomic number 118). Therefore you can directly look for atomic number 15 to find Phosphorus on periodic table.

Another way to read periodic table and locate an element is by using group number (column) and period number (row). To locate Phosphorus on periodic table look for cross section of group 15 and period 3 in the modern periodic table

Phosphorus Facts

Atomic Symbol
Atomic Number
Atomic Weight
other nonmetal
Group in Periodic Table
Group Name
nitrogen family
Block in Periodic Table
Period in Periodic Table
Electronic Configuration
[Ne] 3s2 3p3
Melting Point
44.2 °C
Boiling Point
280.5 °C
Electronic Shell Structure
[2, 8, 5]
CAS Number

Phosphorus Atomic Structure and Orbital Properties

Phosphorus atoms have 15 electrons and the electronic shell structure is [2, 8, 5] with Atomic Term Symbol (Quantum Numbers) 4S3/2.

Phosphorus atomic structure
Phosphorus Isotopes

Element Properties

Atomic Number
Number of Protons
Mass Number
Number of Neutrons
Shell structure (Electrons per energy level)
[2, 8, 5]
Electron Configuration
[Ne] 3s2 3p3
Valence Electrons
3s2 3p3
Oxidation State
-3;-2;-1 1;2;3;4;5
Atomic Term Symbol (Quantum Numbers)


Atomic Structure of Phosphorus

Atomic Radius
98 pm (0.98 Å)
Atomic Volume
16.9905436094 cm33
Covalent Radius
106 pm (1.06 Å)
Van der Waals Radius
180 pm
Neutron Cross Section
0.18 σa/barns

Crystal Structure of Phosphorus

The solid state structure of Phosphorus is Simple Triclinic.

The Crystal structure can be described in terms of its unit Cell. The unit Cells repeats itself in three dimensional space to form the structure

The unit cell is represented in terms of its lattice parameters, which are the lengths of the cell edges Lattice Constants (a=1145, b=550.3 & c=1126.1 pm and the angles between them Lattice Angles (alpha=1.25384, beta=1.57725 and gamma=1.24896).

The symmetry properties of the crystal are described by the concept of space groups. All possible symmetric arrangements of particles in three-dimensional space are described by the 230 space groups (219 distinct types, or 230 if chiral copies are considered distinct.

Space Group Name

Space Group Number

Crystal Structure



Simple Triclinic

Ground State Electronic Configuration of Phosphorus - neutral Phosphorus atom

The ground state electronic configuration of Neutral Phosphorus atom is [Ne] 3s2 3p3. The portion of Phosphorus configuration that is equivalent to the noble gas of the preceding period, is abbreviated as [Ne]. For atoms with many electrons, this notation can become lengthy and so an abbreviated notation is used.This is important as it is the Valence electrons 3s2 3p3, electrons in the outermost shell that determine the chemical properties of the element.

Unabbreviated electronic configuration of neutral Phosphorus

Complete ground state electronic configuration for the Phosphorus atom, Unabbreviated electronic configuration

1s2 2s2 2p6 3s2 3p3

Regulatory and Health - Health and Safety Parameters and Guidelines

CAS Number
RTECS Number
{N/A, RTECSTH3495000, RTECSTH3500000, N/A}
EU Number
{N/A, N/A, N/A, N/A}
DOT Hazard Class
{N/A, 4.1, 4.2, N/A}
DOT Numbers
“N/A”, {1338}, {1381, 2447}, “N/A”
NFPA Fire Rating
{N/A, 0, 4, N/A}
NFPA Hazards
Autoignition Point
400 °C
NFPA Health Rating
{N/A, 0, 4, N/A}
NFPA Reactivity Rating
{N/A, 2, 2, N/A}

Phosphorus Chemical Properties : Phosphorus Ionization Energies and electron affinity

72 kJ/mol

Phosphorus Physical & Elastic Properties

1.823 g/cm3
Molar Volume
16.9905436094 g/cm3
Young Modulus
Shear Modulus
Bulk Modulus
11 GPa
Poisson Ratio

Phosphorus Electrical Properties

Electrical Conductivity
1×107 S/m
1×10-7 m Ω
Superconducting Point

Phosphorus Magnetic Properties

Magnetic Type
Curie Point
Mass Magnetic Susceptibility
Molar Magnetic Susceptibility
Volume Magnetic Susceptibility

Phosphorus Thermal Properties

Magnetic Type
317.3 K (44.2 °C)
Boiling Point
553.6 K (280.5 °C)
Critical Temperature
Superconducting Point

Use of Phosphorus

The main use of phosphorus, in the form of concentrated phosphoric acid, in fertilizers. Phosphorus compounds are also used in baking powder, pesticides, detergents, and plasticisers. The main function of phosphorus is in the formation of bones and teeth. It plays an important role in how the body uses carbohydrates and fats. It is also needed for the body to make protein for the growth, maintenance, and repair of cells and tissues. 

106. Seaborgium [Sg]