Alkenes And Ethanol Flashcards
What type of bond do alkenes have?
A c=c double bond
What is an alkene?
A hydrocarbon which has a double bond between two or the carbon atoms in their chain
Why are they known as unsaturated?
Because they could make more bonds if the double bond opened up it would allow two carbon atoms to bond with other atoms
What are alkenes general formula?
CnH2n
What are the first two alkenes?
Ethene and propene
What is the formula for ethene?
C2H4
What is the formula for propene?
C3H6
How can you test for an alkene?
Adding the substance to bromine water
An alkene will decolourise the bromine water turning it from orange to colourless
This is because the double bond has opened up and formed bonds with bromine
How can ethene be reacted with steam to produce ethanol?
Ethene can be hydrated with steam in the presence of a catalyst to make ethanol
What is the problem with reacting ethene to make ethanol?
Ethene is produced from crude oil which is non renewable so it may become expensive
What is the word equation for ethanol being produced by renewable resources such as fermentation?
Sugar –> carbon dioxide+ethanol
What are the advantages of fermentation?
This process needs a lower temperature ands simpler equipment
It’s a renewable resource (sugar)
Ethanol produced this way can be a cheap fuel
What is the disadvantages of producing ethanol through fermentation?
The ethanol you get from this process isn’t very concentrated so to increase its strength you may need to distill it
It needs to be purified
