Iodine (I) – Periodic Table [Element Information & More]

iodine element periodic table

Iodine element (I) is in group 17 and period 5 of a periodic table. Iodine is in the p-block and it is classified as a halogen group element on the periodic table.

There is a lot more information related to iodine which is mentioned in the Information Table given below.

So let’s dive right into it!

Table of contents

Iodine Element (Information Table)

The important data related to iodine element is given in the table below.

Appearance of iodineSolid iodine has Lustrous gray color
Liquid iodine has Violet color
Gaseous iodine has Violet color
Atomic number of iodine53
Symbol of iodineI
Atomic mass of iodine126.90 u
Protons, Neutrons & Electrons in iodineProtons: 53, Neutrons: 74, Electrons: 53
State of iodine (at STP)Solid
Group number of iodine in periodic table17
Period number of iodine in periodic table5
Block of iodine in periodic tablep-block
Category of iodineNonmetals (halogens)
Bohr model or Electrons per shell or Electrons arrangement in iodine2, 8, 18, 18, 7
Electron configuration of iodine[Kr] 4d10 5s2 5p5
Orbital diagram of iodineorbital diagram of iodine
Valence electrons in iodine7
Electronegativity of iodine (on pauling scale)2.66
Atomic radius of iodine (van der Waals radius)198 picometers
Density of iodine4.94 g/cm3
1st ionization energy of iodine10.451 eV
Main isotope of iodine127I
Melting point of iodine (I2)386.8 K or 113.7 °C or 236.6 °F
Boiling point of iodine (I2)457.4 K or 184.3 °C or 363.7 °F
Crystal structure of iodineOrthorhombic
Discovery of iodineBy Bernard Courtois in 1811

Also see: Interactive Periodic Table (It has rotating bohr models as well as many other details of all the 118 elements in a single periodic table).

Iodine element in Periodic table

The Iodine element (I) has the atomic number 53 and is located in group 17 and period 5. Iodine is a nonmetal and it is classified as a halogen element.

Click on above elements in the periodic table to see their information.

Facts about iodine

Here are a few interesting facts about the iodine element.

  1. Iodine was given its name from the Greek word “iodes” (which means violet color).
  2. Iodine is the 47th abundant element present in the solar system.
  3. Iodine is the 61st abundant element found from the earth’s crust.
  4. There is a lot of iodine present in the sea water (around 34.5 million tons of iodine is in seawater).
  5. The river water contains around 5 parts per billion while the sea water contains around 50-60 parts per billion of iodine.
  6. Iodine is also present  in our surroundings like plants, animals, soil, etc.

Properties of iodine

Here is a list of some physical properties and chemical properties of iodine.

Physical properties of iodine

  • Iodine is solid at room temperature and it has a shiny gray surface.
  • The density of iodine is 4.94 g/cm3 and its atomic mass is 126.90 u.
  • The melting point and boiling point of iodine is 386.8 K and 457.4 K respectively.
  • Iodine has many isotopes, and out of these isotopes, the stable isotope is 127I.
  • The crystal structure of iodine is Orthorhombic.

Chemical properties of iodine

  • Iodine is a reactive nonmetal and hence it is always found in compounds with other metals.
  • Iodine is less soluble in water but it is more soluble in nonpolar solvents.
  • Iodine reacts with metals and forms salts.
  • The iodine has electronegativity of 2.66 on a pauling scale.
  • Pure iodine can burn the skin.

Uses of iodine

Here are some uses of the iodine element.

  • The iodine is present in table salt (and our body gets the required iodine from table salt).
  • Iodine is also used in the manufacturing of acetic acid.
  • Radioactive isotope if iodine (131I) can be used to cure cancer of the thyroid gland.
  • Some antiseptics also contain iodine which kills the bacteria and germs.

External resources:

  1. Iodine – Wikipedia. (2017, November 20). Iodine – Wikipedia.
  2. Iodine – Element information, properties and uses | Periodic Table. (n.d.). Iodine – Element Information, Properties and Uses | Periodic Table.
  3. P. (n.d.). Iodine | I (Element) – PubChem. Iodine | I (Element) – PubChem.
  4. Prohaska, T., et al. (2022, May 1). Standard atomic weights of the elements 2021 (IUPAC Technical Report). Pure and Applied Chemistry, 94(5), 573–600.
  5. Haynes, W. M. (Ed.). (2014, June 4). CRC Handbook of Chemistry and Physics.
  6. Kaye, G W.C., & Laby, T H. Tables of physical and chemical constants. 15th Edition. United States.
  7. Sansonetti, J. E., & Martin, W. C. (2005, December). Handbook of Basic Atomic Spectroscopic Data. Journal of Physical and Chemical Reference Data, 34(4), 1559–2259.
  8. Periodic Table of Elements: Los Alamos National Laboratory. (n.d.). Periodic Table of Elements: Los Alamos National Laboratory.
  9. Atomic Data for Iodine (I ). (n.d.). Atomic Data for Iodine (I ).
  10. Atomic Weight of Iodine | Commission on Isotopic Abundances and Atomic Weights. (n.d.). Atomic Weight of Iodine | Commission on Isotopic Abundances and Atomic Weights.
  11. Bondi, A. (1964, March). van der Waals Volumes and Radii. The Journal of Physical Chemistry, 68(3), 441–451.
  12. Holden, et al. (2018, December 1). IUPAC Periodic Table of the Elements and Isotopes (IPTEI) for the Education Community (IUPAC Technical Report). Pure and Applied Chemistry, 90(12), 1833–2092.
  13. Zhang, et al. (2011, January 11). Corrected Values for Boiling Points and Enthalpies of Vaporization of Elements in Handbooks. Journal of Chemical & Engineering Data, 56(2), 328–337.
  14. Atomic Iodine | I | ChemSpider. (n.d.). Atomic Iodine | I | ChemSpider.
  16. It’s Elemental – The Element Iodine. (n.d.). It’s Elemental – the Element Iodine.

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