Answer is: Far greater than 118 because elements combine in various ways.
Number of compounds is more than 30 millions.
A chemical compound is a substance composed of many identical molecules.
Element bonded to an identical chemical element is not a compound.
For example, emerald (beryl) is chemical compound (beryllium aluminium cyclosilicate) with the chemical formula Be₃Al₂(SiO₃)₆.
Other example, molecule carbon(IV) oxide (CO₂) is made of one carbon atom and two oxygen atoms bonded with covalent bonds.
Element is pure substance is made of only one type of atom (element) or only one type of molecule, it has definite and constant composition with distinct chemical properties.
