Iodine Atomic Number

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  • Iodine (atomic symbol: I, atomic number: 53) is a Block P, Group 17, Period 5 element with an atomic radius of 126.90447. The number of electrons in each of Iodine's shells is 2, 8, 18, 18, 7 and its electron configuration is Kr 4d 10 5s 2 5p 5. The iodine atom has a radius of.
  • Electron configuration and elemental properties of iodine. (Image credit: Greg Robson/Creative Commons, Andrei Marincas Shutterstock) Just the facts. Atomic number (number of protons in the.

We elaborate the uses of Iodine and atomic properties with characteristics. Iodine is a chemical element with a violet appearance (Gas) Violet gray (Solid) with atomic number 53. Its symbol is I and it belongs to the group of halogens and its usual state in nature is solid. Iodine is located at position 53 on the periodic table.

Atomic Number of Iodine Iodine is a chemical element with atomic number 53 which means there are 53 protons and 53 electrons in the atomic structure. The chemical symbol for Iodine is I.

Iodine is a chemical element with the atomic number of 53. The chief store-house of iodine in the body is the thyroid gland. The essential thyroxin, which is secreted by this gland, is made by the circulating iodine. Iodine atomic number: 53 atomic radius: 140 pm ionization energy of iodine: first- 1008.4 second- 1845.9 electron affinity: 3.0590463 Ionic radius: 220 valence electrons: 7 electronegativity: 2.66 iodine is a P block element on the periodic table of elements history of iodine.

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On this page you can discover the chemical properties of iodine and information about iodine and other elements of the periodic table such as bromine, astate, tellurium or xenon. You will also learn what iodine is for and you will know what its uses through its properties associated with iodine such as its atomic number or the usual state in which iodine can be found.

You will be able to see qualities of iodine such as its melting and boiling point, its magnetic properties or what its chemical symbol is. Also, here you will find information about its atomic properties such as the distribution of electrons in iodine atoms and other properties.

For some elements, part of this information is unknown. In these cases we show the properties attributed to them.

Properties of iodine

Elements of the group of halogens such as iodine occur as chemically active diatomic molecules. The name halogen comes from the Greek and its meaning is “salt former”. They are halogen elements, including iodine, they are oxidants. Many organic synthetic compounds and some natural organic compounds contain halogens such as iodine. These types of compounds are known as halogenated compounds.

The state of iodine in its natural form is solid. Iodine is a chemical element with a violet appearance (Gas) Purplish gray (Solid) and belongs to the group of halogens. The atomic number of iodine is 53. The chemical symbol for iodine is I. The melting point of iodine is 355.95 degrees Kelvin or 83.8 degrees Celsius, or degrees Centigrade. The boiling point of iodine is 457.4 degrees Kelvin or 185.25 degrees Celsius or degrees Centigrade.

Iodine is a mineral that our body needs for its proper functioning and can be found in food. Through the following link, you can find a list of foods with iodine .

Atomic Properties of Iodine

The atomic mass of an element is determined by the total mass of neutrons and protons that can be found in a single atom belonging to this element. Regarding the position where to find iodine within the periodic table of elements, iodine is found in group 17 and period 5. Iodine has an atomic mass of 126.90447 u.

The electron configuration of iodine is [Kr] 4d105s25p5. The electronic configuration of the elements determines the way in which the electrons are structured in the atoms of an element. The mean radius of iodine is 140 pm, its atomic radius or Bohr radius is 115 pm, its covalent radius is 133 pm, and its Van der Waals radius is 198 pm. Iodine has a total of 53 electrons whose distribution is as follows: In the first shell it has 2 electrons, in the second it has 8 electrons, in its third shell it has 18 electrons, in the fourth, 18 electrons and in the fifth shell it has 7 electrons.

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Characteristics of iodine

Below you can see a table that shows the main characteristics of iodine.

Chemical symbolI
Atomic number53
AppearanceViolet (Gas) Violet gray (Solid)
Density4,940 kg / m3
Atomic mass126.90447 u
Medium radius140 pm
Atomic radio115
Covalent radius133 pm
Van der Waals radio198 pm
Electronic configuration[Kr] 4d105s25p5
Electrons per shell2, 8, 18, 18, 7
Oxidation states-1, 1, 3, 5, 7
Oxidestrong acid
Crystal structureorthorhombic
Melting point355.95 K
Boiling point457.4 K
Heat of fusion7,824 kJ / mol
Specific heat145 J / (Kkg)
Electric conductivity8.0 × 10-8S / m
Thermal conductivity0.449 W / (Km)

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Element Iodine - I

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

  • Atomic Number: 53
  • Group: 17
  • Period: 5
  • Series: Halogens

Electrons In Iodine

Iodine's Name in Other Languages

  • Latin: Iodum
  • Czech: Jod
  • Croatian: Jod
  • French: Iode
  • German: Jod - r
  • Italian: Iodio
  • Norwegian: Jod
  • Portuguese: Iôdo
  • Russian: Иод
  • Spanish: Yodo
  • Swedish: Jod

Atomic Structure of Iodine

  • Atomic Radius: 1.32Å
  • Atomic Volume: 25.74cm3/mol
  • Covalent Radius: 1.33Å
  • Cross Section (Thermal Neutron Capture) σa/barns: 6.2
  • Crystal Structure: Orthorhombic
  • Electron Configuration:
    1s2 2s2p6 3s2p6d10 4s2p6d10 5s2p5
  • Electrons per Energy Level: 2,8,18,18,7
    Shell Model
  • Ionic Radius: 2.2Å
  • Filling Orbital: 5p5
  • Number of Electrons (with no charge): 53
  • Number of Neutrons (most common/stable nuclide): 74
  • Number of Protons: 53
  • Oxidation States:±1,5,7
  • Valence Electrons: 5s2p5
    Electron Dot Model

Chemical Properties of Iodine

  • Electrochemical Equivalent: 4.7348g/amp-hr
  • Electron Work Function:
  • Electronegativity: 2.66 (Pauling); 2.21 (Allrod Rochow)
  • Heat of Fusion: 7.824kJ/mol
  • Incompatibilities:
    Ammonia, acetylene, acetaldehyde, powdered aluminum, active metals, liquid chlorine
  • Ionization Potential
    • First: 10.451
    • Second: 19.131
    • Third: 33
  • Valence Electron Potential (-eV): -6.55

Physical Properties of Iodine

  • Atomic Mass Average: 126.9045
  • Boiling Point: 458.55K 185.4°C 365.7°F
  • Coefficient of lineal thermal expansion/K-1: N/A
  • Conductivity
    Electrical: 8.0E-16 106/cm Ω
    Thermal: 0.00449 W/cmk
  • Density: 4.93g/cc @ 300K
  • Description:
    Halogen solid form: shiny, non-metallic, grayish-black flakes; gas: violet.
  • Elastic Modulus:
    • Bulk: 7.7/GPa
  • Enthalpy of Atomization: 106.7 kJ/mole @ 25°C
  • Enthalpy of Fusion: 7.76 kJ/mole
  • Enthalpy of Vaporization: 20.88 kJ/mole
  • Flammablity Class: Non-combustible solid
  • Freezing Point:see melting point
  • Heat of Vaporization: 20.752kJ/mol
  • Melting Point: 386.65K 113.5°C 236.3°F
  • Molar Volume: 25.74 cm3/mole
  • Physical State (at 20°C & 1atm): Solid
  • Specific Heat: 0.214J/gK

Regulatory / Health

  • CAS Number
    • 7553-56-2
  • RTECS: NN1575000
  • OSHAPermissible Exposure Limit (PEL)
    • 1 ppm = 10.38mg/m3 @ 25°C & 1 atm
    • Ceiling: 0.1 ppm
  • OSHA PEL Vacated 1989
    • Ceiling: 0.1 ppm
  • NIOSHRecommended Exposure Limit (REL)
    • Ceiling: 0.1 ppm
    • IDLH: 2 ppm
  • Routes of Exposure: Inhalation; Ingestion; Skin and/or eye contact
  • Target Organs: Eyes, skin, respiratory system, central nervous system, cardiovascular system
  • 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: 0.057
    • Bone/p.p.m: 0.27
    • Liver/p.p.m: 0.7
    • Muscle/p.p.m: 0.05-0.5
    • Daily Dietary Intake: 0.1-0.2 mg
    • Total Mass In Avg. 70kg human: 12-20 mg

Who / Where / When / How

  • Discoverer: Bernard Courtois
  • Discovery Location: Dijon France
  • Discovery Year: 1811
  • Name Origin:
    Greek: iôdes (violet).
  • Abundance of Iodine:
    • Earth's Crust/p.p.m.: 0.14
    • Seawater/p.p.m.:
      • Atlantic Suface: 0.0489
      • Atlantic Deep: 0.056
      • Pacific Surface: 0.043
      • Pacific Deep: 0.058
    • Atmosphere/p.p.m.: N/A
    • Sun (Relative to H=1E12): N/A
  • Sources of Iodine:
    Occurs on land and in the sea in sodium and potassium compounds. World production of iodine is around 12,000 tons. Primary producing areas are Chile and Japan.
  • Uses of Iodine:
    Required in small amounts by humans. Once used as an antiseptic, but no longer due to its poisonous nature. Used as a disinfectant, in pharmaceuticals, dyes, catalysts and photography.
  • Additional Notes:

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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.

Iodine 129 Atomic Number

Iodine Atomic Number

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Kenneth Barbalace. Periodic Table of Elements - Iodine - I. 1995 - 2021. Accessed on-line: 4/24/2021

Iodine Atomic Number And Symbol

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Iodine 125 Atomic Number

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