Oxidation Number

[DanielHong2L]

What's an oxidation number? How do you find it for a specific atom?

[Hasmik Dis 2F]

An oxidation number is basically the electron amount that an atom gains/loses whenever forming a bond with other atoms. There's usually set guidelines for assigning oxidation numbers. For example, group one is always +1, group 2 is +2, oxygen is always -2 (except for in hydrogen peroxide). There's many exceptions that you can just memorize and it'll help you get the hang of it!

[Jason_John_2F]

oxidation number is the charge of specific atoms that make up the compound which shows how many electrons each atom has gained or lossed when forming bonds

[ellenulitsky Dis 1I]

The oxidation number of a free element is always 0 and the oxidation number of a monatomic ion equals the charge of the ion, which is found in the periodic table.

[MCalcagnie_ 1D]

Do you think we will need to have these oxidation numbers memorized for future? Or do you think they will be given? I am not sure if Dr. Lavelle specified this.

[Serena Song 1A]

To add on, for polyatomic ions, the sum of oxidation numbers should equal the charge of the ion. For example, in sulfate (SO4^2-), we know that the sum of the oxidation numbers should equal -2 and that the oxidation number for O is -2. We can get the equation X +4(-2) = -2 where X equals the oxidation number of sulfur. Therefore, the oxidation number of sulfur in sulfate is +6.

[MMorcus2E]

I think that we should know the general rules but I doubt that we will need to have them memorized, like with single atoms, polyatomic atoms, or depending on column numbers. Oxidation numbers can also be found on some periodic tables.

[Ayesha Aslam-Mir 3C]

Does an oxidation number pertain to both loss and gain? How does it relate to reduciton?

[MCalcagnie_ 1D]

I think that we should know the general rules but I doubt that we will need to have them memorized, like with single atoms, polyatomic atoms, or depending on column numbers. Oxidation numbers can also be found on some periodic tables.

Okay perfect thank you for your clarification!!

[Taber Ball 1F]

Hi! I was also confused about what an oxidation number is and how to find it. Everyone's posts were very helpful. Just checking my understanding:

An oxidation number is the amount of electrons that an atom gains or loses when forming a bond with another atom. There are set rules to assigning oxidation numbers and several exceptions which can be memorized. General rules pertain to single atoms, polyatomic atoms, or column numbers and are sometimes included in periodic tables.

Please let me know if this looks like an accurate summation and feel free to share anything I should add! Thank you!