Answer:
Atomic number is the number of electrons or number of protons. That's why neon have ten number of electrons.
Step-by-step explanation:
An atom consist of electron, protons and neutrons. Protons and neutrons are present with in nucleus while the electrons are present out side the nucleus.
All these three subatomic particles construct an atom. A neutral atom have equal number of proton and electron. In other words we can say that negative and positive charges are equal in magnitude and cancel the each other. For example if neutral atom has 6 protons than it must have 6 electrons. The sum of neutrons and protons is the mass number of an atom while the number of protons are number of electrons is the atomic number of an atom.
For example
The neon have ten protons and ten neutrons so its atomic mass is 20 amu and atomic number is ten.