What is the chemical formula for ammonia?

Ammonia is a simple molecule consisting of one nitrogen atom and three hydrogen atoms. The correct chemical formula for ammonia is written as NH3, which indicates that each ammonia molecule is made up of one nitrogen atom covalently bonded to three hydrogen atoms.

In this context, NH4OH represents ammonium hydroxide, which is a different compound, while N2H4 is hydrazine, which contains two nitrogen atoms and is structurally distinct from ammonia. NH2Cl is an amine derivative known as chloramine, which also has a different structure and chemical properties compared to ammonia. Therefore, the formula NH3 accurately conveys the composition of ammonia, making it the correct answer.