Nucleons + electrons; isotopes

HideShow resource information

Protons, neutrons, electrons; isotopes

The protons and neutrons are in the centre of the atom, held together by a force called strong nuclear force.

This is much stronger than the electrostatic forces of attraction that hold electrons and protons together in the atom.

Atomic number Z = number of protons (proton number)

Mass number A = number of protons + neutrons

 Protons and neutrons are called nucleons.

1 of 2

Protons, neutrons, electrons; isotopes

Different isotopes of the same element react chemically in exactly the same way as they have the same electron configuration.

Relative atomic mass (Ar) is the average mass of one atom compared to 1/12 mass of an atom of carbon-12.

Relative molecular mass (Mr) is the average mass of one molecule compared to 1/12 mass of one atom of carbon-12.

Atomic orbital is a region of space around an atomic nucleus where there is a high probability of finding an electron.

2 of 2


No comments have yet been made

Similar Chemistry resources:

See all Chemistry resources »See all Atomic structure resources »