In this post, we will determine the oxidation numbers in hydroxylamine, NH2OH.

To determine the oxidation number of an atom(s) in a molecule or an ion, start with the known oxidation numbers and the rules summarized below:



Keep in mind that the summary is zero for neutral molecules and is equal to the charge for ions.

For NH2OH, the elements with standard oxidation states are oxygen (-2), and hydrogen (+1), so we need to determine the oxidation state of the nitrogen. 

Assign x for the oxidation state of N and set up an equation:

1(x) + 2(+1) + 1(-2) + 1(+1)= 0

x + 2 -2 +1= 0

x = -1

We can also assign the oxidation state of the hydroxide ion -1 as if it is a monoatomic ion (rule 2), and set up another equation:

1(x) + 2(+1) + 1(-1) = 0

x = -1


Further Reading


More examples of the oxidation state in this multiple-choice quiz:


Oxidation State and Redox Reactions Quiz


Reactions in Aqueous Solutions Quiz

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