Group 9 element

Group 9 in the periodic table
Hydrogen Helium
Lithium Beryllium Boron Carbon Nitrogen Oxygen Fluorine Neon
Sodium Magnesium Aluminium Silicon Phosphorus Sulfur Chlorine Argon
Potassium Calcium Scandium Titanium Vanadium Chromium Manganese Iron Cobalt Nickel Copper Zinc Gallium Germanium Arsenic Selenium Bromine Krypton
Rubidium Strontium Yttrium Zirconium Niobium Molybdenum Technetium Ruthenium Rhodium Palladium Silver Cadmium Indium Tin Antimony Tellurium Iodine Xenon
Caesium Barium Lanthanum Cerium Praseodymium Neodymium Promethium Samarium Europium Gadolinium Terbium Dysprosium Holmium Erbium Thulium Ytterbium Lutetium Hafnium Tantalum Tungsten Rhenium Osmium Iridium Platinum Gold Mercury (element) Thallium Lead Bismuth Polonium Astatine Radon
Francium Radium Actinium Thorium Protactinium Uranium Neptunium Plutonium Americium Curium Berkelium Californium Einsteinium Fermium Mendelevium Nobelium Lawrencium Rutherfordium Dubnium Seaborgium Bohrium Hassium Meitnerium Darmstadtium Roentgenium Copernicium Nihonium Flerovium Moscovium Livermorium Tennessine Oganesson
group 8 ←    → group 10
IUPAC group number 9
Name by element cobalt group
CAS group number
(US, pattern A-B-A)
 part of VIIIB
old IUPAC number
(Europe, pattern A-B)
 part of VIII
↓ Period
4
Image: Cobalt, electrolytic made, 99,9%
Cobalt (Co)
27 Transition metal
5
Image: Rhodium, powder, pressed, remelted 99,99%
Rhodium (Rh)
45 Transition metal
6
Image: Pieces of pure iridium
Iridium (Ir)
77 Transition metal
7 Meitnerium (Mt)
109 unknown chemical properties

Legend

primordial element
synthetic element

Group 9, by modern IUPAC numbering,[1] is a group (column) of chemical elements in the d-block of the periodic table. Members of Group 9 include cobalt (Co), rhodium (Rh), iridium (Ir) and meitnerium (Mt).[2] These elements are among the rarest of the transition metals.[3]

Like other groups, the members of this family show patterns in electron configuration, especially in the outermost shells, resulting in trends in chemical behavior; however, rhodium deviates from the pattern.

  1. ^ Fluck, E. (1988). "New Notations in the Periodic Table" (PDF). Pure Appl. Chem. 60 (3): 431–436. doi:10.1351/pac198860030431. S2CID 96704008. Retrieved 24 March 2012.
  2. ^ Leigh, G. J. Nomenclature of Inorganic Chemistry: Recommendations 1990. Blackwell Science, 1990. p. 283. ISBN 0-632-02494-1.
  3. ^ "Group 9: Transition Metals". Chemistry LibreTexts. 2020-08-15. Retrieved 2022-03-24.