A compound is a substance that has two or more chemical elements whose atoms are bonded together. These atoms are chemically bonded in specific ways and in detailed proportions, and the substances cannot be readily separated through simple physical means.
1. Water - Formula: H2O = Hydrogen2 + Oxygen
Two atoms of the element Hydrogen combine with one atom of Oxygen through a covalent bond to form water. Hydrogen has a slightly positive charge and oxygen has a negative charge, and therefore it forms a polar molecule. Water can be split back into hydrogen and oxygen through electrolysis.