Ethane is colourless gas, the representative of a class of alkanes having chemical formula C2H6. Ethylene – also colourless gas, but, unlike ethane, in the nature is almost not presented. This substance - the most ordinary representative related to alkanes of a class of alkenes, that is hydrocarbons in which molecule there is a double communication. It is almost insoluble in water, it is well dissolved in acetone, some air.
Instruction
1. In industrial conditions ethylene synthesize by pyrolysis of various hydrocarbons, first of all, the same ethane. Reaction goes thus: C2H6 = C2H4 + H2
2. Also pyrolysis can subject propane and butane, indispensable components of associated gases of oil production. As raw materials for receiving ethylene not only gases, but also liquid fractions of direct distillation of oil can serve.
3. But also the return task can be sometimes set: to receive ethane from ethylene. Certainly, in the industry nobody will be engaged in absolutely absurd, unprofitable business. And in laboratory practice, for evident confirmation of properties of ethylene, it is quite real. How it is possible to carry out similar transformation?
4. It is enough to look at formulas of these two substances to receive the answer. Thanks to existence in a molecule of double communication, ethylene can attach two more ions of hydrogen. That is, it is necessary to carry out hydrogenation reaction: C2H4 + H2 = C2H6 This reaction goes at the increased temperature and pressure, with use of nickel catalysts.