Atoms consist of : Electrons which have a -1 negative charge, Neutrons which are neutral and Protons which a +1 charge.
- The total number of electrons in an atom is the same as the number of protons in the nucleus.
- The number of protons in an atom is called its atomic number (the top number in the periodic table)
Electrons are arranged in different shells around the nucleus
Maximum Number of electrons in a shell --> First-2 Second-8 Third-8 Fourth-18 (Whatever the number is in the outer shell then that is what group it is in)
Ions are electrically charged particles formed when atoms lose or gain electrons