Answer:
Atomic number
Protons
Step-by-step explanation:
Elements generally have specific atomic number of protons they are made up of.
An element is a distinct substance that cannot be split-up into simpler substances. Such substance are made up of only one kind of atom.
- Each element has a unique atomic number
- The atomic number is used to differentiate between an element or the other.
- The atomic number is the number of protons in an atom.