oxidation state

American  

noun

Chemistry.

1. the state of an element or ion in a compound with regard to the electrons gained or lost by the element or ion in the reaction that formed the compound, expressed as a positive or negative number indicating the ionic charge of the element or ion.

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oxidation state Scientific  

1. See valence

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Etymology

Origin of oxidation state

First recorded in 1945–50

Example Sentences

See Examples For:

oxidation state

"Uranium usually occurs with a valency of 4 or 6. Pentavalent uranium does exist, but it is rare or only transient. Until now, it had been seen in an unstable oxidation state," explains Newman-Portela.

From Science Daily ● Aug. 9, 2026

If synthesized in a normal atmosphere, manganese and iron would continue binding with oxygen and shift to a higher oxidation state, preventing the material from forming correctly.

From Science Daily ● Dec. 4, 2025

"This is an unusual observation for a molecular system based on manganese in its oxidation state +IV. Even with noble metals emission in this energy region is essentially unprecedented," said Professor Katja Heinze.

From Science Daily ● Feb. 9, 2024

Tin and lead form the stable divalent cations, Sn2+ and Pb2+, with oxidation states two below the group oxidation state of 4+.

From Textbooks ● Feb. 14, 2019

The stability of this oxidation state is a consequence of the inert pair effect.

From Textbooks ● Feb. 14, 2019