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 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 because the iridium resulting from this interaction was in the rare and highly active +6 oxidation state."

From Science Daily • May 9, 2024

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

The oxidation state of the metal becomes positive as it undergoes oxidation and that of the nonmetal becomes negative as it undergoes reduction.

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