Mass number will help you. Mass number is the total of neutrons and protons.
mass number = protons + nuetrons
The mass number
The atomic number of aluminium is 13. So it has 13 protons and 13 electrons.
mass number = protons + nuetrons
atomic number is the number of protons. the sum of protons and neutrons is known as mass number
mass number
12,13, and 26
The Mass Number.
by number of protons and nuetrons
since there are 22 protons there has to be 22 nuetrons since there are 22 protons there has to be 22 nuetrons
well you look at the periodic table of elements. the atomic number equals the number of protons. Then subtract the number of protons from the atomic mass (both protons and nuetrons have atomic mass units of 1 and electrons equal 0). That will give you the number of nuetrons.
An element can be identified by the number of protons in the nucleus of its atoms.