Phosphorus Chemical Properties (25 Facts You Should Know)

Phosphorus is a chemical element present in the periodic table. Here, let us discuss some special features of the Phosphorous element.

Phosphorous is a vital element for all living beings as it is present in the DNA and RNA in the form of phosphate sugar. There are 3 types of phosphorus with 3 different colors i.e., red, white (or yellow), and black (or violet) phosphorus. All these phosphorus has different melting points and also they are lustrous.

Let us discuss the details about the atomic number, electronegativity, melting point, boiling point, and various chemical properties of phosphorus and some facts about it.

Phosphorus symbol

The chemical symbolic notation of the Phosphorus element is ‘P’.

Phosphorus group in the periodic table

The Phosphorus element has occupied the place in the 15th group of the periodic table. It is present below nitrogen and above arsenic elements.

Phosphorus period in the periodic table

The Phosphorus element has occupied the place in 3rd period of the periodic table. It is present after silicon and before sulfur elements.

Phosphorous element

Phosphorus block in the periodic table

The Phosphorus element comes under the p-block elements of the periodic table.

Phosphorus atomic number

The Phosphorus element has the atomic number 15, i.e., there is a total of 15 protons in its nucleus.

Phosphorus Atomic Weight

The Phosphorus element has an atomic weight of 30.973762 u.

Phosphorus Electronegativity according to Pauling

According to Pauling’s scale, the Phosphorus atom has an electronegativity value of 2.19.

Phosphorus atomic Density

The different types of Phosphorus elements have the atomic density as follows:

  • White phosphorus: 1.823 g/cm3
  • Red phosphorus: ≈2.2–2.34 g/cm3 
  • Violet phosphorus: 2.36 g/cm3 
  • Black phosphorus: 2.69 g/cm3

Phosphorus melting point

The Phosphorus element has the melting point value of 44.15 °C (317.3 K, 111.47°F).

Phosphorus boiling point

The Phosphorus element gets boiled at a temperature of 280.5°C (553.7 K, 536.9°F).

Phosphorus Vanderwaals radius

The Phosphorus element has the VanderWaals radius of 180 pm.

Phosphorus ionic/covalent radius

The covalent and ionic radius of phosphorus element is listed below:

  • The Phosphorus element has a covalent radius of 111 pm.
  • The phosphorus element has an ionic radius of 58 pm at +3 oxidation state and 52 at +5 oxidation state.

Phosphorus isotopes

The atoms of the same element have different neutron numbers but similar proton numbers are called isotopes. Let us discuss the isotopes of the Phosphorus element.

The naturally occurring Phosphorus 15P has only one stable isotope and various unstable isotopes. The isotopes of phosphorus is given below.

Isotopes of Phosphorus elementCharacteristics
Phosphorus 31 – 31PMost stable isotope of the Phosphorus element
Phosphorus 33 – 33PLongest live isotope of Phosphorus element with a half-life period of 24.34 days
Phosphorus 32 – 32PIsotope of Phosphorus with a half-life value of 14.268 days
Phosphorus 25 – 25PIsotope of Phosphorus with a half-life value of shorter than 30 nanoseconds
Isotopes of phosphorous

Phosphorus electronic shell

The presence of electrons in the orbitals or shells of atoms in a sequential manner is called the electronic shell. The electronic shell of the phosphorus element is discussed below.

The Phosphorus element has the electronic shell of 2, 8, and 5.

Phosphorus energy of first ionization

The Phosphorus metal has the first ionization energy value of 1011.812 kJ mol‑1.

Phosphorus energy of second ionization

The Phosphorus metal has the second ionization energy value of 1907.467 kJ mol‑1.

Phosphorus energy of third ionization

Phosphorus metal has the third ionization energy value of 2914.118 kJ mol‑1.

Phosphorus oxidation states

The Phosphorus atom can show the oxidation states of  −3, −2, −1, 0, +1, +2, +3, +4, and +5, but the -3, +3, and -5 are the most common oxidation states of phosphorus.

Phosphorus electron configurations

The Phosphorus atom has an electronic configuration as below:

  • 1s22s22p63s23p3or
  • [Ne] 3s² 3p³

Phosphorus CAS number

The Phosphorus atom has the CAS number 7723-14-0.

Phosphorus ChemSpider ID

The Phosphorus atom has the ChemSpider ID 4575369.

Phosphorus allotropic forms

The atoms of similar elements that show different structural forms are called the allotropes of that element. There are three main allotropes of phosphorus element given below:

  • White P is a white waxy translucent solid and glows in dark conditions.
  • Red P is iron-grey lustrous color but does not glow in the dark and is insoluble in water.
  • Black P is 2 types of black P i.e., α and, ß black P, and formed by heating red P at different temperatures.

Phosphorus chemical classification

The Phosphorus element gets classified as a more reactive non-metallic element.

Phosphorus state at room temperature

The Phosphorus element shows the solid (transparent waxy solid) state at room temperature.

Is Phosphorus paramagnetic?

The presence of paired electrons shows the diamagnetic nature of an element. Let us see if Phosphorus element is diamagnetic in nature.

Phosphorus is diamagnetic in nature and not paramagnetic. It occurs in P4 form thus it shows diamagnetic nature even if it has three unpaired electrons. On applying an external magnetic field it get repel each other and shows a diamagnetic character.


Phosphorous is symbolized as P and has the atomic number 15. It has an electronegativity of 2.91 and belongs to the 15th group and third periods of the periodic table. It has common oxidation states of -3, +3, and +5. It is diamagnetic in nature.

Read more about Iodine Chemical Properties.

Read more following properties

Aluminium hydrides
Aluminium Chemical Properties
Magnesium hydride(MgH2)
Phosphorus Triiodide(PI3)
Boron Chemical
Nitrogen Dioxide(NO2)
Phosphorus Trichloride(PCl3)
Sulfur Trioxide(SO3)
Carbon Tetrafluoride (CF4)
Propanoic Acid (CH3CH2COOH)
Barium Hydroxide(Ba(OH)2)
Silicon Chemical Properties

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