what is the differences between ethane and ethene?

Ethane is a chemical compound with chemical formula C2H6. It is the only two-carbon alkane, that is, an aliphatic hydrocarbon. At standard temperature and pressure, ethane is a colorless, odorless gas.
Ethane is isolated on an industrial scale from natural gas, and as a byproduct of petroleum refining. Its chief use is as petrochemical feedstock for ethylene production.
Ethylene (or IUPAC name ethene) is the chemical compound with the formula C2H4. It is the simplest alkene. Because it contains a double bond, ethylene is called an unsaturated hydrocarbon or an olefin. It is extremely important in industry and even has a role in biology as a hormone.Ethylene is the most produced organic compound in the world; global production of ethylene exceeded 75 million metric tonnes per year in 2005.

最重要既分別：
ethene 係有 carbon-carbon double bond.
但係 ethane 就無。

佢地既eqt係如下
ethane-----C2H6
ethene-----C2H4

ethane 是　乙烷
而ethene是　乙烯