The number of protons in an atom's nucleus determines its chemical identity.
the number of protons determines the atom.
The atomic number, which is the number of protons in the nucleus, determines what kind of atom it is.
Number of protons or the atomic number of an atom determines what is the element.
protons + neutrons.
Mass Number
An atom has the same number of electrons as it does protons, and the number of protons determines what element it is.
The number of protons in the nucleus of an atom determines the atomic number of the element to which the atom belongs.
The number of protons.
Atomic Number
This is the number of protons.
Its atomic number. In other words the number of positive protons in the nucleus of each atom and the number of negative electrons surrounding the nucleus of each atom.