1. Assign Oxidation Numbers to Hydrogen:
* Hydrogen typically has an oxidation number of +1, unless it's bonded to a metal, in which case it's -1.
* In N₂H₄, hydrogen is bonded to nonmetals, so its oxidation number is +1.
2. Set up the Equation:
* Let the oxidation number of nitrogen be represented by "x".
* We have two nitrogen atoms (2x) and four hydrogen atoms (4 * +1).
* The overall charge of the molecule is 0.
3. The Equation:
2x + (4 * +1) = 0
4. Solve for x:
* 2x + 4 = 0
* 2x = -4
* x = -2
Therefore, the oxidation number of nitrogen (N) in hydrazine (N₂H₄) is -2.
