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

To stabilize these ceramics, manganese and iron atoms must remain in the 2+ oxidation state, forming what is known as a rock salt structure where each atom bonds with only two oxygen atoms.

From Science Daily • Dec. 4, 2025

To verify that manganese and iron truly remained in the intended oxidation state, Almishal collaborated with researchers at Virginia Tech.

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

Remember that an element exhibits a positive oxidation state when combined with a more electronegative element and that it exhibits a negative oxidation state when combined with a less electronegative element.

From Textbooks • Feb. 14, 2019

Aluminum normally uses all of its valence electrons when it reacts, giving compounds in which it has an oxidation state of 3+.

From Textbooks • Feb. 14, 2019