Fe Mass Number

Posted : admin On 1/29/2022

Element Iron - Fe

  1. Mass Number For Fe
  2. What Is The Mass Of Fe
  3. Element Fe
  4. 56 Fe Mass Number
  5. Fe Mass Number

Comprehensive data on the chemical element Iron is provided on this page; including scores of properties, element names in many languages, most known nuclides of Iron. 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.

Iron Menu

Iron-56 (56 Fe) is the most common isotope of iron. About 91.754% of all iron is iron-56. Of all nuclides, iron-56 has the lowest mass per nucleon. With 8.8 MeV binding energy per nucleon, iron-56 is one of the most tightly bound nuclei. Hey, 56 is the mass. Now Fe is the symbol for iron. Its atomic number is 26 so thats how many protons there are. Then you take 56-36=30. Thats to find the neutrons (30). And since its not an ion. The isotope 56 Fe is the isotope with the lowest mass per nucleon, 930.412 MeV/c 2, though not the isotope with the highest nuclear binding energy per nucleon, which is nickel-62.

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Overview of Iron

  • Atomic Number: 26
  • Group: 8
  • Period: 4
  • Series: Transition Metals

Iron's Name in Other Languages

Mass Number For Fe

  • Latin: Ferrum
  • Czech: Železo
  • Croatian: Željezo
  • French: Fer
  • German: Eisen - s
  • Italian: Ferro
  • Norwegian: Jern
  • Portuguese: Ferro
  • Russian: Железо
  • Spanish: Hierro
  • Swedish: Järn

Atomic Structure of Iron

  • Atomic Radius: 1.72Å
  • Atomic Volume: 7.1cm3/mol
  • Covalent Radius: 1.17Å
  • Cross Section (Thermal Neutron Capture)σa/barns: 2.56
  • Crystal Structure: Cubic body centered
  • Electron Configuration:
    1s2 2s2p6 3s2p6d6 4s2
  • Electrons per Energy Level: 2,8,14,2
    Shell Model
  • Ionic Radius: 0.645Å
  • Filling Orbital: 3d6
  • Number of Electrons (with no charge): 26
  • Number of Neutrons (most common/stable nuclide): 30
  • Number of Protons: 26
  • Oxidation States: 2,3
  • Valence Electrons: 3d6 4s2
    Electron Dot Model

Chemical Properties of Iron

  • Electrochemical Equivalent: 0.69455g/amp-hr
  • Electron Work Function: 4.7eV
  • Electronegativity: 1.83 (Pauling); 1.64 (Allrod Rochow)
  • Heat of Fusion: 13.8kJ/mol
  • Incompatibilities:
  • Ionization Potential
    • First: 7.87
    • Second: 16.18
    • Third: 30.651
  • Valence Electron Potential (-eV): 67

Physical Properties of Iron


What Is The Mass Of Fe

Fe element mass number
  • Atomic Mass Average: 55.847
  • Boiling Point: 3023K 2750°C 4982°F
  • Coefficient of lineal thermal expansion/K-1: 12.3E-6
  • Conductivity
    Electrical: 0.0993 106/cm Ω
    Thermal: 0.802 W/cmK
  • Density: 7.874g/cc @ 300K
  • Description:
    Pure iron is lustrous, silvery and easy to work. Iron easily rusts in damp air.
  • Elastic Modulus:
    • Bulk: 170/GPa
    • Rigidity: 82/GPa
    • Youngs: 211/GPa
  • Enthalpy of Atomization: 414.2 kJ/mole @ 25°C
  • Enthalpy of Fusion: 14.9 kJ/mole
  • Enthalpy of Vaporization: 351 kJ/mole
  • Flammablity Class:
  • Freezing Point:see melting point
  • Hardness Scale
    • Brinell: 490 MN m-2
    • Mohs: 4
    • Vickers: 608 MN m-2
  • Heat of Vaporization: 349.6kJ/mol
  • Melting Point: 1808K 1535°C 2795°F
  • Molar Volume: 7.11 cm3/mole
  • Optical Reflectivity: 65%
  • Physical State (at 20°C & 1atm): Solid
  • Specific Heat: 0.44J/gK
  • Vapor Pressure = [email protected]°C

Regulatory / Health

  • CAS Number
    • 7439-89-6
  • OSHAPermissible Exposure Limit (PEL)
    • No limits set by OSHA
  • OSHA PEL Vacated 1989
    • No limits set by OSHA
  • NIOSHRecommended Exposure Limit (REL)
    • No limits set by NIOSH
  • 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: 447
    • Bone/p.p.m: 3-380
    • Liver/p.p.m: 250-1400
    • Muscle/p.p.m: 180
    • Daily Dietary Intake: 6-40 mg
    • Total Mass In Avg. 70kg human: 4.2 g
  • Discovery Year: Unknown
  • Name Origin:
    Latin, ferrum; Anglo-Saxon, iron
  • Abundance of Iron:
    • Earth's Crust/p.p.m.: 41000
    • Seawater/p.p.m.:
      • Atlantic Suface: 0.0001
      • Atlantic Deep: 0.0004
      • Pacific Surface: 0.00001
      • Pacific Deep: 0.0001
    • Atmosphere/p.p.m.: N/A
    • Sun (Relative to H=1E12): 3.16E+07
  • Sources of Iron:
    Obtained from hematite, magnetite, goethite, lepidocrocite and siderite. Annual world production is around 716,000,000 tons. Primary areas iron is mined are USA, Canada, Sweden, South Africa, Russia, India and Japan.
  • Uses of Iron:
    Used in steel and other alloys which are used in countless products. It is essential for animals as it is the chief constituent of hemoglobin which carries oxygen in blood vessels. Iron is the most important element of all the metals.
  • Additional Notes:
    Deficiency of iron leads to anaemia, but excess iron in the body causes liver and kidney damage.

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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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    Answers many questions regarding the structure of atoms.
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    Introduces stoichiometry and explains the differences between molarity, molality and normality.
  • Molar Mass Calculations and Javascript Calculator
    Molar mass calculations are explained and there is a JavaScript calculator to aid calculations.
  • Chemical Database
    This database focuses on the most common chemical compounds used in the home and industry.

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Element Fe

<a href='https://EnvironmentalChemistry.com/yogi/periodic/Fe.html'>echo Periodic Table of Elements: Iron - Fe (EnvironmentalChemistry.com)</a>- Comprehensive information for the element Iron - Fe is provided by this page including scores of properties, element names in many languages, most known nuclides and technical terms are linked to their definitions.


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Iron-56, 56Fe
Namesiron-56, Fe-56
Nuclide data
Natural abundance91.754%
Isotope mass55.9349375(7)u
Excess energy−60601.003± 1.354 keV
Binding energy492253.892± 1.356 keV
Isotopes of iron
Complete table of nuclides
Nuclear binding energy per nucleon of common isotopes; iron-56 labelled at the curve's crest. The rarer isotopes nickel-62 and iron-58, which both have higher binding energies, are not shown.

Iron-56 (56Fe) is the most common isotope of iron. About 91.754% of all iron is iron-56.

Of all nuclides, iron-56 has the lowest mass per nucleon. With 8.8 MeVbinding energy per nucleon, iron-56 is one of the most tightly bound nuclei.[1]

Nickel-62, a relatively rare isotope of nickel, has a higher nuclear binding energy per nucleon; this is consistent with having a higher mass-per-nucleon because nickel-62 has a greater proportion of neutrons, which are slightly more massive than protons. (See the nickel-62 article for more). Light elements undergoing nuclear fusion and heavy elements undergoing nuclear fission release energy as their nucleons bind more tightly, so 62Ni might be expected to be common. However, during nucleosynthesis in stars the competition between photodisintegration and alpha capturing causes more 56Ni to be produced than 62Ni (56Fe is produced later in the star's ejection shell as 56Ni decays).

Fe Mass Number

Production of these elements has decreased considerably from what it was at the beginning of the stelliferous era.[citation needed]

Nonetheless, 28 atoms of nickel-62 fusing into 31 atoms of iron-56 releases 0.011 u of energy. As the Universe ages, matter will slowly convert to ever more tightly bound nuclei, approaching 56Fe, ultimately leading to the formation of iron stars over ≈101500 years in an expanding universe without proton decay.[2]

See also[edit]


  1. ^Nuclear Binding Energy
  2. ^Dyson, Freeman J. (1979). 'Time without end: Physics and biology in an open universe'. Reviews of Modern Physics. 51 (3): 447–460. Bibcode:1979RvMP...51..447D. doi:10.1103/RevModPhys.51.447.

56 Fe Mass Number

  • de Laeter, John Robert; Böhlke, John Karl; De Bièvre, Paul; Hidaka, Hiroshi; Peiser, H. Steffen; Rosman, Kevin J. R.; Taylor, Philip D. P. (2003). 'Atomic weights of the elements. Review 2000 (IUPAC Technical Report)'. Pure and Applied Chemistry. 75 (6): 683–800. doi:10.1351/pac200375060683.
Iron-56 is an
isotope of iron
Decay product of:
Decay chain
of iron-56
Decays to:
Fe Mass Number

Fe Mass Number

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