Bonds

There are 2 types of bonds:
- covalent bond
- ionic bond

covalent bond is a bond between 2 non-metals
ionic bond is a bond between a metal and a non-metal

in ionic bond, the metal looses an electron to the non-metal while in covalent the non-metals share their valence electrons

cation: when an atom looses its electron (s), becoming positively charged
anion: when an atom gains electron (s), becoming negatively charged

Electronegativity: attraction between an atom and the bonding electron (s). It only occurs in covalent bonds not ionic bonds. When there is an unequal attraction between two bonding atoms, it is called the polar covalent bond. When it is equal, it is known as the non-polar covalent bond.

Hydrogen bond: attractive interaction of a hydrogen atom with an electronegative atom (also called the intermolecular bond).
There are 3 types of intermolecular bond (Van Der Waals Forces).
1. London forces
2. Dipole - dipole forces
3. Hydrogen bonds