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  1. State that ethanol may be formed by reaction between ethene and steam.

As we saw in the previous topic, ethene undergoes an addition reaction with steam to form alcohol.
C2H4 + H20  ———–>  C2H5OH

  1. Describe the formation of ethanol by the catalytic addition of steam to ethene.

A high temperature is required for this reaction to break the double bonds of  the carbon in the ethene. Steam is passed over a catalyst of concentrated phosphoric acid, to speed up the reaction. The water (H2O) atoms join with the ethene(C2H5) by breaking the double bonds to form ethanol(C2H5OH).

  1.  Describe the complete combustion reaction of ethanol.

Ethanol burns with a clear blue flame in excess air to form carbon dioxide:
C2H5OH  +  3O2 ———-> 2CO2  +  3H2O

  1. State the uses of ethanol as a solvent and as a fuel.

As a solvent: used in perfumes and other cosmetics, in printing inks and in glues

As a fuel: mixed with petrol or used alone as a fuel for cars. It is less polluting than petrol and reduces the reliance on petrol and diesel.



Notes submitted by Lintha

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