1: Atomic Structure

1.1 Inside the Atom Sub-atomic particles Electrons revolve around in region of space called   Electrons do not move in fixed   The nucleus is made up of protons and neutrons which contains almost all the mass of the atom. This is because the mass of...

1.2    Isotopes Isotopes   Isotopes are atoms of the same element with the same number of proton but different number of   Example: Isotopes have the same: number of protons and electrons electronic configuration chemical properties(because they have the...