Lesson 6: Reactions of alkenes Flashcards

1
Q

What are alkenes?

A
  • Alkenes are hydrocarbons with a double carbon- carnon bond.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is the general formula for the homologous series of alkenes?

A

CnH2n

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Why are alkenes known as “unsaturated” hydrocarbons?

A
  • Alkenes are “unsaturated” because they contain two fewer hydrogen atoms than the alkane with the same number of carbon atoms.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What are the first 4 members of the homologous series of alkenes?

A
  • Ethene
  • Propene
  • Butene
  • Pentene
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What function group do alkenes contain?

A

C=C

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What determines the reactions of organic compounds?

A
  • Generally the reactions of functional groups determine the reactions of organic compounds.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

How do alkenes react with oxygen? How do they react with this oxygen differently to other hydrocarbons?

A
  • Alkenes react with oxygen in combustion reactions in the same way as other hydrocarbons.
  • They tend to burn in air with smoky flames because of incomplete combustion (carbon soot produced.)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

How do alkenes react with hydrogen, water and halogens?

A
  • Alkenes react with hydrogen, water and halogens by the addition of atoms across the carbon-carbon double bond so that the double bond becomes a single carbon-carbon bond.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is a “functional group” of a molecule?

A
  • A functional group (of a molecule) determines how the molecule reacts.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is the product when an alkene reacts with hydrogen?

A

Alkene + hydrogen —> alkane

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What are the conditions needed for an alkene to react with hydrogen to form an alkane?

A
  • 150⁰C
  • Nickel catalyst.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is the reaction of an alkene with hydrogen called?

A
  • Hydrogenation.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is the reaction of an alkene with water called?

A
  • Hydration
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What are the 4 conditions required for the hydration reaction of an alkene?

A
  • Water (that is reacting with the alkene) must be in the form of steam.
  • 300⁰C
  • Pressure = 70 atmospheres.
  • Phosphoric acid catalyst (to increase yield of alcohol, any unreacted alkene and steam are passed back through the catalyst.)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What type of reaction is a hydration reaction?

A
  • Hydration reaction is a reversible reaction.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is the general equation for the reaction of an alkene with water (steam)?

A

Alkene + water (steam) —-> alcohol

17
Q

What is the general formula for an alkene reacting with a halogen?

A

Alkene + halogen —> DIhalogenalkane
Ie.
Ethene + chlorine —> dichloroethane
Ethene + bromine —> dibromoethane
Ethene + iodine —> diiodethane

18
Q

What is the name of the reaction that ADDS hydrogen, halogens and water to an alkene?

A
  • Addition reactions