Phosphorus Atomic Number


Phosphorus (atomic number 15, symbol P) is a non-metal with a monoclinic structure and 3 main allotropes - black, red, and white. It has 3 oxidation states - 5, 4, 3 and is a multivalent non-mental. The element occurs in the form of phosphates, as organophosphates, and in minerals. 15: Phosphorus - Phosphorous P Group: 15 Period: 3 Atomic number: 15 Atomic mass: 30.973762 Configuration: Ne 3s 2 3p 3 Atomic radius: 98 pm Covalent radius: 107 pm Electron affinity: 72 eV Ionization energy: 10.4867 eV Electronic term: 4 S 3/2 Mass fraction in the earth crust: 0.00099 Mass fraction in the earth space: 0.000007. Isotopes of Phosphorus There are twenty-three isotopes of phosphorus, that range in atomic numbers from 26 to 43. Natural phosphorus constitutes only one stable isotope, phosphorus-31.

Element Phosphorus - P

Comprehensive data on the chemical element Phosphorus is provided on this page; including scores of properties, element names in many languages, most known nuclides of Phosphorus. Common chemical compounds are also provided for many elements. In addition technical terms are linked to their definitions and the menu contains links to related articles that are a great aid in one's studies.

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Overview of Phosphorus

  • Atomic Number: 15
  • Group: 15
  • Period: 3
  • Series: Nonmetals
Phosphorus Atomic Number

Phosphorus's Name in Other Languages

  • Latin: Phosphorus
  • Czech: Fosfor
  • Croatian: Fosfor
  • French: Phosphore
  • German: Phosphor - r
  • Italian: Fosforo
  • Norwegian: Fosfor
  • Portuguese: Fósforo
  • Russian: Фосфор
  • Spanish: Fósforo
  • Swedish: Fosfor

Atomic Structure of Phosphorus

  • Atomic Radius: 1.23Å
  • Atomic Volume: 17cm3/mol
  • Covalent Radius: 1.06Å
  • Cross Section (Thermal Neutron Capture) σa/barns: 0.172
  • Crystal Structure: Monoclinic
  • Electron Configuration:
    1s2 2s2p6 3s2p3
  • Electrons per Energy Level: 2,8,5
    Shell Model
  • Ionic Radius: 0.38Å
  • Filling Orbital: 3p3
  • Number of Electrons (with no charge): 15
  • Number of Neutrons (most common/stable nuclide): 16
  • Number of Protons: 15
  • Oxidation States: ±3,5,4
  • Valence Electrons: 3s2p3
    Electron Dot Model

Chemical Properties of Phosphorus

  • Electrochemical Equivalent: 0.23113g/amp-hr
  • Electron Work Function:
  • Electronegativity: 2.19 (Pauling); 2.06 (Allrod Rochow)
  • Heat of Fusion: 0.657kJ/mol
  • Incompatibilities:
    Air, oxidizers (including elemental sulfur & strong caustics), halogens
  • Ionization Potential
    • First: 10.486
    • Second: 19.725
    • Third: 30.18
  • Valence Electron Potential (-eV): 190

Physical Properties of Phosphorus

  • Atomic Mass Average: 30.97376
  • Boiling Point: 553K 280°C 536°F
  • Coefficient of lineal thermal expansion/K-1: 124.5E-6
  • Conductivity
    Electrical: 1.0E-17 106/cm Ω
    Thermal: 0.00235 W/cmk
  • Density: 1.82g/cc @ 300K
  • Description:
    Soft white waxy solid, brownish-red powder or black solid.
  • Elastic Modulus:
    • Bulk: 11/GPa
  • Enthalpy of Atomization: 314.6 kJ/mole @ 25°C
  • Enthalpy of Fusion: 0.63 kJ/mole
  • Enthalpy of Vaporization: 12.43 kJ/mole
  • Flammablity Class: Flammable solid
  • Freezing Point:see melting point
  • Heat of Vaporization: 12.129kJ/mol
  • Melting Point: 317.45K 44.3°C 111.7°F
  • Molar Volume: 17 cm3/mole
  • Optical Refractive Index: 1.001212
  • Physical State (at 20°C & 1atm): Solid
  • Specific Heat: 0.77J/gK
  • Vapor Pressure = [email protected]°C

Regulatory / Health

  • CAS Number
    • 7723-14-0
  • UN/NA ID and ERG Guide Number
    • 1381 / 136
  • RTECS: TH3500000
  • OSHAPermissible Exposure Limit (PEL)
    • TWA: 0.1 mg/m3
  • OSHA PEL Vacated 1989
    • TWA: 0.1 mg/m3
  • NIOSHRecommended Exposure Limit (REL)
    • TWA: 0.1 mg/m3
    • IDLH: 5 mg/m3
  • Routes of Exposure: Inhalation; Ingestion; Skin and/or eye contact
  • Target Organs: Eyes, skin, respiratory system, liver, kidneys, jaw, teeth, blood
  • Levels In Humans:
    Note: this data represents naturally occuring levels of elements in the typical human, it DOES NOT represent recommended daily allowances.
    • Blood/mg dm-3: 345
    • Bone/p.p.m: 67000-71000
    • Liver/p.p.m: 3-8.5
    • Muscle/p.p.m: 3000-8500
    • Daily Dietary Intake: 900-1900 mg
    • Total Mass In Avg. 70kg human: 780 g

Who / Where / When / How

  • Discoverer: Hennig Brand
  • Discovery Location: Hamburg Germany
  • Discovery Year: 1669
  • Name Origin:
    Greek: phôs (light) and phoros (bearer).
  • Abundance of Phosphorus:
    • Earth's Crust/p.p.m.: 1000
    • Seawater/p.p.m.:
      • Atlantic Suface: 0.0015
      • Atlantic Deep: 0.042
      • Pacific Surface: 0.0015
      • Pacific Deep: 0.084
    • Atmosphere/p.p.m.: N/A
    • Sun (Relative to H=1E12): 316000
  • Sources of Phosphorus:
    Found most often in phosphate rock. Annual world wide production is around 153,000,000 tons. Primary mining areas are Russia, USA, Morocco, Tunisia, Tongo and Nauru.
  • Uses of Phosphorus:
    Used in the production of fertilizers, fireworks, matches, pesticides, toothpaste and detergents.
  • Additional Notes:
    White phosphorus is much more toxic than red phosphorus. Necrosis of the jaw, also called phossy-jaw, is caused by chronic exposure to white phosphorus.

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A list of reference sources used to compile the data provided on our periodic table of elements can be found on the main periodic table page.

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Phosphorus 32 Atomic Number

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In the modern periodic table, the elements are listed in order of increasing atomic number. The atomic number is the number of protons in the nucleus of an atom. The number of protons define the identity of an element (i.e., an element with 6 protons is a carbon atom, no matter how many neutrons may be present). The number of protons determines how many electrons surround the nucleus, and it is the arrangement of these electrons that determines most of the chemical behavior of an element.

In a periodic table arranged in order of increasing atomic number, elements having similar chemical properties naturally line up in the same column (group). For instance, all of the elements in Group 1A are relatively soft metals, react violently with water, and form 1+ charges; all of the elements in Group 8A are unreactive, monatomic gases at room temperature, etc. In other words, there is a periodic repetition of the properties of the chemical elements with increasing mass.

Phosphorus Atomic Number And Atomic Mass

In the original periodic table published by Dimitri Mendeleev in 1869, the elements were arranged according to increasing atomic mass— at that time, the nucleus had not yet been discovered, and there was no understanding at all of the interior structure of the atom, so atomic mass was the only guide to use. Once the structure of the nucleus was understood, it became clear that it was the atomic number that governed the properties of the elements.