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- 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
- 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).
- 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
- 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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