Ethylene
General
Molecular formula	C2H4
SMILES	C==C
Molar mass	28.05 g/mol
Appearance	colorless gas
Properties
Density and phase	1.178 kg/m³ at 15 °C, gas
Solubility in water	3.5 mg/100 ml (17 °C)
Melting point	−169.2 °C (104.0 K, -272.6 °F)
Boiling point	−103.7 °C (169.5 K, -154.7 °F)
Structure
Symmetry group	D2h
Dipole moment	Zero

Ethylene or ethene is a chemical compound with two carbon atoms and four hydrogen atoms in each molecule. These molecules are put together with a double bond that makes it a hydrocarbon. It is very important in industry and has even been used in biology as a hormone. It is also the most made chemical. About 75 million tons of it have been made each year since 2005. Its biggest use is to make polyethylene.