Alkenes And Ethanol

Question 1

What type of bond do alkenes have?

Answer 1

A c=c double bond

Question 2

What is an alkene?

Answer 2

A hydrocarbon which has a double bond between two or the carbon atoms in their chain

Question 3

Why are they known as unsaturated?

Answer 3

Because they could make more bonds if the double bond opened up it would allow two carbon atoms to bond with other atoms

Question 4

What are alkenes general formula?

Answer 4

CnH2n

Question 5

What are the first two alkenes?

Answer 5

Ethene and propene

Question 6

What is the formula for ethene?

Answer 6

C2H4

Question 7

What is the formula for propene?

Answer 7

C3H6

Question 8

How can you test for an alkene?

Answer 8

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

Question 9

How can ethene be reacted with steam to produce ethanol?

Answer 9

Ethene can be hydrated with steam in the presence of a catalyst to make ethanol

Question 10

What is the problem with reacting ethene to make ethanol?

Answer 10

Ethene is produced from crude oil which is non renewable so it may become expensive

Question 11

What is the word equation for ethanol being produced by renewable resources such as fermentation?

Answer 11

Sugar –> carbon dioxide+ethanol

Question 12

What are the advantages of fermentation?

Answer 12

This process needs a lower temperature ands simpler equipment
It’s a renewable resource (sugar)
Ethanol produced this way can be a cheap fuel

Question 13

What is the disadvantages of producing ethanol through fermentation?

Answer 13

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