C10. Organic Reactions (Y11 - Spring 1) Flashcards
๐ข What are the 4 Homologous Series
- Alkanes
- Alkenes
- Alochols
- Carboxylic Acids
๐ข Alkanes:
- General Formula
- 1 x C
- 2 x C
- 3 x C
- 4 x C
- 5 x C
General Formula:
CnH2n+2
1 x C:
Methane, CH4
2 x C:
Ethane, C2H6
3 x C:
Propane, C3H8
4 x C:
Butane, C4H10
5 x C:
Pentane, C5H12
๐ Alkenes:
- General Formula
- 1 x C
- 2 x C
- 3 x C
- 4 x C
- 5 x C
General Formula:
CnH2n
1 x C:
Need at least 2 carbon atoms per double carbon bond (c=c)
2 x C:
Ethene, C2H4
3 x C:
Propene, C3H6
4 x C:
Butene, C4H8
5 x C:
Pentene, C5H10
๐ Alcohols:
- General Formula
- 1 x C
- 2 x C
- 3 x C
- 4 x C
- 5 x C
General Formula:
CnH2n+1OH
1 x C:
Methanol, CH3OH
2 x C:
Ethanol, CH3CH2OH
3 x C:
Propanol, CH3C2H4OH
4 x C:
Butanol, CH3C3H6OH
- 5 x C:*
- Pentanol, CH3C4H8OH*
๐ Carbolxylic Acids (n=0)
- General Formula
- 1 x C
- 2 x C
- 3 x C
- 4 x C
- 5 x C
General Formula:
CnH2n+1COOH
1 x C:
Methanoic Acid, COOH
2 x C:
Ethanoic Acid, CH3COOH
3 x C:
Propanoic Acid, C2H5COOH
4 x C:
Butanoic Acid, C3H7COOH
- 5 x C:*
- Pentanoic Acid, C4H9COOH*
๐ข Formula and Displayed Formula of Methane
CH4
H | H - C - H | H
๐ข Formula and Displayed Formula of Ethane
C2H6
H H | | H - C - C - H | | H H
๐ข Formula and Displayed Formula of Propane
C3H8
H H H | | | H - C - C - C - H | | | H H H
๐ข Formula and Displayed Formula of Butane
C4H10
H H H H | | | | H - C - C - C - C - H | | | | H H H H
๐ข Formula and Displayed Formula of Pentane
C5H12
H H H H H | | | | | H - C - C - C - C - C - H | | | | | H H H H H
๐ Formula and Displayed Formula of Methene
Doesnโt exist
Needs at least 2 carbon atoms per double carbon bond (c=c)
๐ Formula and Displayed Formula of Ethene
C2H4
H H | | C = C | | H H
๐ Formula and Displayed Formula of Propene
C3H6
H H | | C = C - C - H | | | H H H
๐ Formula and Displayed Formula of Butene
C4H8
H H H | | | C = C - C - C - H | | | | H H H H
๐ Formula and Displayed Formula of Pentene
C5H10
H H H H | | | | C = C - C - C - C | | | | | H H H H H
๐ Formula and Displayed Formula of Methanol
CH3OH
H | H - C - O - H | H
๐ Formula and Displayed Formula of Ethanol
CH3CH2OH
H H | | H - C - C - O - H | | H H
๐ Formula and Displayed Formula of Propanol
CH3C2H4OH
H H H | | | H - C - C - C - O - H | | | H H H
๐ Formula and Displayed Formula of Butanol
CH3C3H6OH
H H H H | | | | H - C - C - C - C - O - H | | | | H H H H
๐ Formula and Displayed Formula of Methanoic Acid
COOH
C = O | O - H
๐ Formula and Displayed Formula of Ethanoic Acid
CH3COOH
H | H - C - C = O | | H O - H
๐ Formula and Displayed Formula of Propanoic Acid
C2H5COOH
H H | | H - C - C - C = O | | | H H O - H
๐ Formula and Displayed Formula of Butanoic Acid
C3H7COOH
H H H | | | H - C - C - C - C = O | | | | H H H O - H
๐ How does the reaction of Alkenes with Halogens work (Halogenation)
When you test ethene with bromine water, it reacts. Ethene takes the orange colour out of the reaction mixture and leaves it colourless. The orange colour in bromine water comes from Br2 (aq) molecules, which are converted into colourless product, called dibromoethane, when they react with ethene.
Ethene + Bromine โ> Dibromoethane
C2H4 + Br2 โ> C2H4Br2
๐ How does the reaction of Alkenes with Hydrogen work (Hydrogenation)
The alkenes are unsaturated compounds, because of the C=C bond, their molecules do not contain the maximum number of hydrogen atoms possible in a hydrocarbon molecule. But the addition of a hydrogen molecule, H2, across the double bond will form a saturated hydrocarbon - an alkane. The reaction takes place at 60ยฐC in the presence of a nickel catalyst. For example:
Penatene + Hydrogen โ> (catalyst) pentane
C5H10 + H2 โ> C5H12
๐ Alkene reaction with Hydrogen
What temperature and catalyst is used
The reaction takes place at 60ยฐC in the presence of a nickel catalyst.
๐ What can an Alkene reaction with hydrogen be used for (Hydration)
This reaction is used to add hydrogen across the C=C bonds in unsaturated oils to traighten their molecules and increase their melting points. For example, the right amount of hydrogen is added to make a marharine that can be spread easily straight from the fridge.
๐ How does the reaction of Alkenes with Water (steam) work
Ethanol (an alcohol) for industrial use as a fuel or solvent can be made from ethene gas. Ethene is the main by-product produced in cracking. Ethene gas can react with steam to make ethanol.
Ethene + Steam โ (catalyst) Ethanol
C2H4 + H2O โ C2H5OH
The reaction requires energy to heat the gases and to generate a high pressure. The reaction is reversible, so ethanol can break back down into ethene and steam. So unreacted ethene and steam are recycled over the catalyst.
๐ What is Ethanol used for?
Ethanol (an alcohol) for industrial use as a fuel or solvent can be made from ethene gas. Ethene is the main by-product produced in cracking.
๐ What are the required conditions for an Akene to react with water (steam) (+how can this be recycled?)
The reaction requires energy to heat the gases and to generate a high pressure. The reaction is reversible, so ethanol can break back down into ethene and steam. So unreacted ethene and steam are recycled over the catalyst.