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Glite Dictionary
oxidation number

oxidation number

1 7.2
A number that shows how many electrons an atom has lost or gained in compounds and ions
  • noun
  • /ˌɑksɪˈdeɪʃən ˈnʌmbər/
  • Specialized
translation icon : número de oxidación
  • In chemistry class, we learned how to determine the oxidation number of various elements in compounds.

Examples

  • The oxidation number for oxygen in water is typically -2.

  • So why don't you tell me what the oxidation number is for this now?

  • So then we need to figure out what the oxidation number of cobalt is first.

  • To find the oxidation number of an atom, you must consider its charge and the number of bonds it forms.

Synonyms

oxidation state
vsoxidation number
  • Specialized
1 6.3

A number that shows how many electrons an atom has gained, lost, or shared when it joins other atoms

is a formal assigned value usually matching the ionic charge for simple ions

Surface Forms

oxidation number singular
oxidation numbers plural

Morphology

oxidation + number

The phrase is compositionally transparent in that it literally means a number related to oxidation, so a B1 learner who knows 'oxidation' and 'number' can infer it denotes a numeric value indicating an atom's degree of oxidation. However, the precise technical sense (how the number is assigned, sign conventions, and equivalence to ionic charge in simple ions) is domain-specific and not fully predictable from the constituent meanings alone.

Etymology

Oxidation number comes from the words oxidation and number and gives a simple picture: imagine giving each atom a score that shows how many tiny electrons it has 'lost' or 'gained'. So the oxidation number is that score and it helps you see how atoms change in chemical reactions.