It is produced by heating either natural gas, especially its ethane and propane components, or petroleum to 800–900 °C (1,470–1,650 °F), giving a mixture of gases from which the ethylene is separated. The melting point of ethylene is −169.4 °C [−272.9 °F], and its boiling point is −103.9 °C [−155.0 °F].