Determine the Oxidation Number of N in N2H4

To determine the oxidation number of nitrogen (N) in hydrazine (N₂H₄), we start by applying some basic rules of oxidation states.

1. **Hydrogen’s Oxidation State**: In most compounds, hydrogen has an oxidation state of +1.

2. **Overall Charge**: The molecule N₂H₄ is neutral, which means the sum of the oxidation states of all atoms must equal zero.

3. **Setting Up the Equation**: We have 2 nitrogen atoms and 4 hydrogen atoms. Let’s denote the oxidation state of nitrogen as x. The equation can be set up as follows:

2x + 4(+1) = 0

4 from hydrogen comes from 4 H atoms, each contributing +1.

4. **Solving the Equation**:

2x + 4 = 0

2x = -4

x = -2

5. **Conclusion**: Therefore, the oxidation number of each nitrogen atom in N₂H₄ is -2.