Cobalt (Co) – Periodic Table [Element Information & More]

Cobalt element (Co) is in group 9 and period 4 of a periodic table. Cobalt is in the d-block and it is classified as a transition element on the periodic table.

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

So let’s dive right into it!

Table of contents

• Cobalt element (Information Table)
• Cobalt element in Periodic table
• Facts about Cobalt
• Properties of Cobalt
• Uses of Cobalt

Cobalt Element (Information Table)

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

Appearance of cobalt	Bluish shiny gray appearance
Atomic number of cobalt	27
Symbol of cobalt	Co
Atomic mass of cobalt	58.933 u
Protons, Neutrons & Electrons in cobalt	Protons: 27, Neutrons: 32, Electrons: 27
State of cobalt (at STP)	Solid
Group number of cobalt in periodic table	9
Period number of cobalt in periodic table	4
Block of cobalt in periodic table	d-block
Category of cobalt	Transition metals
Bohr model or Electrons per shell or Electrons arrangement in cobalt	2, 8, 15, 2
Electron configuration of cobalt	[Ar] 3d7 4s2
Orbital diagram of cobalt
Electronegativity of cobalt (on pauling scale)	1.88
Atomic radius of cobalt (van der Waals radius)	192 picometers
Density of cobalt	8.9 g/cm3
1st ionization energy of cobalt	7.881 eV
Main isotope of cobalt	59Co
Melting point of cobalt	1768 K or 1495 °C or 2723 °F
Boiling point of cobalt	3200 K or 2927 °C or 5301 °F
Crystal structure of cobalt	Hexagonal Close Packing (HCP)
Discovery of cobalt	By Georg Brandt in 1735

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).

Cobalt element in Periodic table

The Cobalt element (Co) has the atomic number 27 and is located in group 9 and period 4. Cobalt is a metal and it is classified as a transition element.

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

Facts about cobalt

Here are a few interesting facts about cobalt element.

1. The name “Cobalt” came from the German word “kobald” (which means “goblin”).
2. The concentration of cobalt in the earth’s crust is around 25 ppm by weight.
3. Cobalt is also present in the human body.
4. 30% of cobalt is used in paints industries as well as ceramics industries.
5. Cobalt is naturally magnetic like iron. Also the cobalt can maintain its magnetism at higher temperatures.
6. Cobalt is obtained as a byproduct while mining copper and nickel.
7. Cobalt is largely produced in Africa.

Properties of cobalt

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

Physical properties of cobalt

• Cobalt has a bluish-gray shiny metallic appearance.
• Cobalt has many isotopes, but the most abundant naturally occurring isotope of cobalt is ⁵⁹Co.
• The density of cobalt is 8.9 g/cm³ and its atomic mass is 58.933 u.
• The melting point and boiling point of cobalt metal is 1768 K and 3200 K respectively.

Chemical properties of cobalt

• If cobalt is kept open in the air, it reacts with the atmospheric oxygen and forms cobalt oxide.
• Cobalt is a fairly reactive transition metal. It is not found in a free state in nature but it is always found as a compound with other elements in the earth’s crust.
• The electron configuration of cobalt is [Ar] 3d⁷ 4s², which shows that it has incompletely filled d-orbitals.

Uses of cobalt

Here are some uses of the cobalt element.

• Cobalt is used in manufacturing superalloys that have anticorrosive properties as well as they are stable to higher temperatures.
• Cobalt is used to make magnets for generators, drives, etc which operates at high temperatures. Because cobalt can retain its magnetism even at higher temperatures.
• Cobalt can give different colors when combined with other elements.
• Cobalt is used in manufacturing of inks, paints, and glass which requires blue coloring agent.
• Cobalt is used with other metals in making some engine parts of aircraft as cobalt can resist high temperatures.
• Cobalt is used in making rechargeable batteries.
• The radioactive isotope of cobalt (i.e ⁶⁰Co) has medical applications to treat cancer tumors.

External resources:

1. Cobalt. (n.d.). Cobalt. https://webbook.nist.gov/cgi/inchi?ID=C7440484&Mask=20
2. C&EN: IT’S ELEMENTAL: THE PERIODIC TABLE – COBALT. (n.d.). C&EN: IT’S ELEMENTAL: THE PERIODIC TABLE – COBALT. https://pubsapp.acs.org/cen/80th/print/cobalt.html?
3. It’s Elemental – The Element Cobalt. (n.d.). It’s Elemental – the Element Cobalt. https://education.jlab.org/itselemental/ele027.html
4. P. (n.d.). Cobalt | Co (Element) – PubChem. Cobalt | Co (Element) – PubChem. https://pubchem.ncbi.nlm.nih.gov/element/Cobalt
5. Cobalt – Wikipedia. (2008, September 19). Cobalt – Wikipedia. https://en.wikipedia.org/wiki/Cobalt
6. Pourret, O., & Faucon, M. P. (2017). Cobalt. Encyclopedia of Earth Sciences Series, 1–4. https://doi.org/10.1007/978-3-319-39193-9_271-2
7. Cobalt | Co | ChemSpider. (n.d.). Cobalt | Co | ChemSpider. http://www.chemspider.com/Chemical-Structure.94547.html?rid=17a2c671-c7b6-4a01-b9e6-90fa812a07bc&page_num=0
8. Haynes, W. M. (Ed.). (2014, June 4). CRC Handbook of Chemistry and Physics. https://doi.org/10.1201/b17118
9. 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. https://doi.org/10.1515/pac-2015-0703
10. Emsley, J. (2011). Nature’s Building Blocks: An A-Z Guide to the Elements. United Kingdom: OUP Oxford.
11. Allred, A. (1961, June). Electronegativity values from thermochemical data. Journal of Inorganic and Nuclear Chemistry, 17(3–4), 215–221. https://doi.org/10.1016/0022-1902(61)80142-5
12. Kaye, G W.C., & Laby, T H. Tables of physical and chemical constants. 15th Edition. United States.
13. 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. https://doi.org/10.1063/1.1800011
14. Bondi, A. (1964, March). van der Waals Volumes and Radii. The Journal of Physical Chemistry, 68(3), 441–451. https://doi.org/10.1021/j100785a001
15. James A. M. & Lord M. P. (1992). Macmillan’s chemical and physical data. Macmillan.
16. Zhang, Y., Evans, J. R. G., & Yang, S. (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. https://doi.org/10.1021/je1011086
17. Possolo, A., van der Veen, A. M. H., Meija, J., & Hibbert, D. B. (2018, January 4). Interpreting and propagating the uncertainty of the standard atomic weights (IUPAC Technical Report). Pure and Applied Chemistry, 90(2), 395–424. https://doi.org/10.1515/pac-2016-0402