In the Redox Reactions chapter of Chemistry, calculating the oxidation number (or oxidation state) of elements within a compound is essential. Let's calculate the oxidation number of Nitrogen in Ammonia (NH₃).
Compound: Ammonia (NH₃) is a neutral molecule.
Oxidation state of Hydrogen: +1.
Oxidation state of Nitrogen: -3.
To find the oxidation number, we use the standard rules for assigning oxidation states:
Let the unknown oxidation number of Nitrogen (N) be x. We have 3 atoms of Hydrogen, each with an oxidation state of +1.
The equation becomes: (Number of N atoms × x) + (Number of H atoms × +1) = 0 1(x) + 3(+1) = 0 x + 3 = 0 x = -3
Therefore, the oxidation number of Nitrogen in NH₃ is -3.
In the ammonia molecule (NH3), the oxidation number of the Nitrogen atom is -3, while the oxidation number for each Hydrogen atom is +1.
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