Ionic bonding

• Transferring electrons
• In ionic bonding, atoms lose or gain electrons to form charged particles called ions
• Ions are strongly attracted to each other because of the attraction of opposite charges + and -
•  

Keen to get rid:

• A shell with just one atom is keen to get rid of it
• All atoms on the left-hand side of the periodic table e.g sodium and potassium have just one or two electrons in their outer shell (highest energy level)
• And so they're pretty keen to get rid of it so they have only full shells left
• Given the chance, they do get rid and that leaves the atom as an ion instead
• They leap at the first passing ion with opposite charge and stick to it like glue

Keen to get that extra electron:

• Atoms on the other side of the periodic table e.g oxygen, have almost full outer shells
• They want to gain an extra one to become full shells and so become ions when they do
• They then latch onto the ion that gave them the elctron a moment earlier