Atomic mass number of the atom. The best way to remember it is: the majority of the mass of an atom is made up of the protons and neutrons (the electrons are very light!), therefore the atomic mass number is the sum of the protons and neutrons.
Mass number = Number of protons + Number of neutrons
The sum of all Protons and Neutrons.
Without knowing which nuclide is in question, it remains safe to say that regardless of the element, in an ion the atomic number or count of protons differs from the number of electrons - and thus the atom is overall not electrically neutral - the definition of an ion. With fewer electrons than protons, it would be a positively charged ion (cation); with more electrons than protons, it would be a negative ion (anion). If the atomic number (proton number) is P, the charge is x and the mass number is M, then protons = P neutrons = M- P and electrons is the algebraic sum of P and x.
Different atoms either have a different number of protons(which makes them different elements) or a different number of neutrons (which makes them isotopes of the same element).For example, hydrogen has one proton (and usually no neutrons) while helium has two protons (and usually two neutrons). However, hydrogen with one proton and two neutrons is called tritium(3H) while helium with two protons and one neutron is called helium-3 (3He).
You can't have that combination. Such an atom wouldn't be stable - not even for a tiny fraction of a second.The atomic mass is the sum of the atomic number (i.e., the number of protons), and the number of neutrons.
neutral
protons will tell the atomic number (8) the sum of protons and neutrons will give the mass number of the element
The sum of protons and neutrons is the atomic mass.
atomic number is the number of protons. the sum of protons and neutrons is known as mass number
Sum of protons and neutrons is the Mass number of the element. The number of protons is equal to the number of electrons. Neutrons and protons are sub atomic particles.
atomic number
Isotopes involve different atomic masses. It is sum of number of protons and neutrons.
Atomic mass is simply the sum of the number of protons and the number of neutrons. If an atom has "A" protons and "B" neutrons, its atomic mass is A + B.
Atomic number is number of protons in an atom while atomic mass is the sum of protons and neutrons in an atom when you subtract you will get the number of neutrons in an atom.
The sum of the numbers of protons and neutrons.
atomic number
Atomic mass is the number of protons and neutrons in an atom.
Atomic number is the number of protons in an atom and atomic mass is the sum of the number of protons and neutrons.