Final answer:
The oxidation state of an individual nitrogen atom in NH4OH is -3, determined by the rules for assigning oxidation states, where hydrogen is +1 and the ammonium ion has an overall charge of +1.
Step-by-step explanation:
The oxidation state of an individual nitrogen atom in NH4OH can be calculated using the rules for assigning oxidation states. The compound NH4OH consists of the ammonium ion (NH4+) and the hydroxide ion (OH-). To find the oxidation state of nitrogen, we consider that hydrogen generally has an oxidation state of +1 when combined with nonmetals and oxygen has an oxidation state of -2. In NH4+, with four hydrogen atoms, each hydrogen atom contributes +1, for a total of +4. To balance this and give the overall charge of the ammonium ion (+1), the nitrogen must have an oxidation state of -3.
Furthermore, in OH-, the oxygen has an oxidation state of -2, and the single hydrogen has an oxidation state of +1. But since we are only interested in the nitrogen atom, we focus only on the NH4+ part of NH4OH. So, the oxidation state of an individual nitrogen atom in NH4OH is -3.