Atomic numbers refer to the number of protons in the nucleus of an atom. Ammonia is made up of:
* Nitrogen (N): Atomic number 7
* Hydrogen (H): Atomic number 1
Therefore, ammonia has three hydrogen atoms (3 x 1 = 3 protons) and one nitrogen atom (1 x 7 = 7 protons), making a total of 10 protons. However, this is not considered an "atomic number" as it refers to the whole molecule, not a single element.
