AP BIOLOGY

Detailed explanation-1: -The total number of protons in the nucleus of an atom gives us the atomic number of that atom. It is represented with the letter ‘Z.’ All the atoms of a particular element have the same number of protons, and hence the same atomic number. Atoms of different elements have different atomic numbers.

Detailed explanation-2: -Since an atom of one element can be distinguished from an atom of another element by the number of protons in its nucleus, scientists are always interested in this number, and how this number differs between different elements. The number of protons in an atom is called its atomic number (Z).

Detailed explanation-3: -The atomic number is the number of protons in an atom of an element. In our example, krypton’s atomic number is 36. This tells us that an atom of krypton has 36 protons in its nucleus. The interesting thing here is that every atom of krypton contains 36 protons.

Detailed explanation-4: -The atomic number is the number of protons in an atom, and isotopes have the same atomic number but differ in the number of neutrons.