What does the atomic number tell you?

atomic number. The number of protons in an atomic nucleus; it indicates the position of an element in the periodic table. The number of protons in the nucleus of an atom. In electrically neutral atoms, this number is also equal to the number of electrons orbiting about the atom's nucleus. read more

The atomic number helps people identify elements according to the number of protons one atom of the element has. It essentially defines the element. While having a neutral charge, it also provides the number of electrons the element has (in one atom). read more

Besides placement on the periodic table the atomic number defines the atom of the element by defining the number of protons in the atom. Carbon - Atomic Number 6 has 6 protons Nitrogen - Atomic NUmber 7 has 7 protons. The proton number and the neutron number combine to provide the atomic mass number of the element. read more

The mass number is the sum of the number of protons and neutrons present in the nucleus of an atom. By subtracting 36 protons from the mass number of 84, it is determined that krypton has 48 neutrons. Atoms may gain or lose neutrons, and these different forms of the element are known as isotopes. read more