8: Oxidation Numbers

What is the oxidation state of hydrogen?

Usually +1

When is the oxidation state for hydrogen not +1?

If hydrogen is part of a binary metal hydride, then the oxidation state is -1

What is fluorine’s oxidation state?

ALWAYS -1

What is the oxidation state of oxygen?

Usually -2

When is the oxidation state of oxygen not -2?

If oxygen is in a peroxide, then the oxidation state is -1.

OR

If oxygen is bound to fluorine, then the oxidation state is +2

Chlorine, bromine and iodine usually have an oxidation number of what?

-1

When do chlorine, bromine and iodine not have an oxidation state of -1?

If in a compound with oxygen

The sum of all oxidation numbers in a neutral compound is what?

0

The oxidation number of an element is what?

0

The sum of all oxidation numbers in a polyatomic ion is what?

Equal to the charge

What is the oxidation number for group 1?

+1

What is the oxidation number for group 2?

+2

What is the oxidation number for group 3?

+3

The number in names like elementate (x) (such as manganite (vi)) refers to what?

The element and not the associated oxygen

What is the name of KMnO4?

Potassium manganate (vii) - the oxidation number of manganese is +7