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

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 study also shows the ability to turn on and off this contact by using light to change the oxidation state of the ferrocene, demonstrating a light-switchable ferrocene-based single-molecule device.

From Science Daily • Mar. 5, 2024

"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

Fluorine does not form compounds in which it exhibits positive oxidation states; oxygen exhibits a positive oxidation state only when combined with fluorine.

From Textbooks • Feb. 14, 2019

In chemical reactions, these metals readily lose both valence electrons to form compounds in which they exhibit an oxidation state of 2+.

From Textbooks • Feb. 14, 2019