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

"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 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

The oxides of the lighter members of each group exhibit the group oxidation state.

From Textbooks • Feb. 14, 2019

For example, molybdenum and tungsten, members of group 6, are limited mostly to an oxidation state of 6+ in aqueous solution.

From Textbooks • Feb. 14, 2019