1. Understand Oxidation Numbers
* Oxidation numbers represent the hypothetical charge an atom would have if all bonds were ionic.
* The sum of oxidation numbers in a neutral compound is always zero.
* Hydrogen typically has an oxidation number of +1 (except in metal hydrides).
2. Apply the Rules
* Let the oxidation number of nitrogen be 'x'.
* There are two nitrogen atoms (2x).
* There are four hydrogen atoms (+4).
* The total oxidation number is 2x + 4 = 0
3. Solve for 'x'
* 2x = -4
* x = -2
Therefore, the oxidation number of nitrogen in hydrazine (N₂H₄) is -2.
