In this post, we will determine the oxidation numbers in hydrazine, N2H4.

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 hydrazine, N2H4, the element with a standard oxidation state is hydrogen which is +1, and we need to determine the oxidation state of the nitrogen. 

Rule 6 – The oxidation number of hydrogen is +1:

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

2(x) + 4(+1) = 0, x = -2


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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