(Topic 7) Organic Chemistry (CGP Book) Flashcards
1
Q
What is a hydro carbon?
A
Any compound formed from carbon and hydrogen atoms only
2
Q
What is general formula of alkanes?
A
CnH2n+2
3
Q
What are alkanes?
A
- homologous series - a group of organic compounds that react in a similar way
- saturated compounds- each carbon atom forms four single covalent bonds
4
Q
Formula of methane?
A
CH4
5
Q
Formula of ethane?
A
C2H6
6
Q
Formula of propane?
A
C3H8
7
Q
Formula of butane?
A
C4H10
8
Q
Properties of a short carbon chain?
A
Less gloopy
Lower boiling points
More flammable
9
Q
Equation for combustion in a hydrocarbon?
A
Hydrocarbon + oxygen -> carbon dioxide + water
10
Q
What is oxidised during combustion?
A
Carbon and hydrogen
11
Q
Waste products in combustion?
A
Water and carbon dioxide
12
Q
Number equation for combustion?
A
Fuel + _O2 -> _CO2 + _H2O
13
Q
What is crude oil
A
- fossil fuel
- formed from plant and animal remains from millions of years ago
- over time high temp and pressure led to formation of crude oil
14
Q
Process of fractional distillation?
A
- oil heated until most gas
- gases enter fractionating column
- in column it is hot at bottom and gradually cooler at top
- longer hydrocarbons have higher boiling points so condense back into liquids and drain out of column early on
- shorter hydrocarbons have lower boiling points so condense and drain later on
- crude oil separated into different fractions
15
Q
Uses of crude oil?
A
Fuel
Petrochemical industry
16
Q
What is cracking?
A
Thermal decomposition reaction (breaking molecules down by heating them)
17
Q
Process of cracking?
A
- heat long chain hydrocarbons to vaporise them
- vapour then passed over a hot powered aluminium oxide catalyst
- long chain molecules split apart on the surface of the specks of catalyst
18
Q
Process of steam cracking?
A
- Vaporise the hydrocarbons
- Mix them with steam
- Heat them to a high temperature
19
Q
What are alkenes?
A
Hydrocarbons that have a double bind between two of the carbon atoms
20
Q
Why are alkenes reactive?
A
C=C double bond can open up to make a single bond allowing two of carbon atoms to bond with other atoms
21
Q
What are first four alkenes?
A
Ethene, Propene, Butene and pentene
22
Q
What are first four alkanes?
A
Methane, ethane, propane, butane
23
Q
Formula of ethene?
A
C2H4 with double bond
24
Q
Formula of propene?
A
C3H6 with double bond
25
Formula of butene?
C4H8 with double bond
26
Formula of pentene?
C5H10 with double bond
27
General formula for alkenes?
CnH2n
28
What happens when alkenes are burnt?
-Undergo incomplete combustion
- Carbon dioxide and water still produced but can also get carbon and carbon monoxide
29
Equation of incomplete combustion?
Alkene + Oxygen -> Carbon + Carbon dioxide + Carbon monoxide + water
30
What does incomplete combustion result in?
Smoky yellow flame and less energy being released
31
What is a functional group?
A group of atoms in a molecule that determine how the molecule typically reacts
All alkenes have C=C so react in a similar way
32
How do alkenes react?
Via addition reactions
33
What happens when alkenes react with steam?
Water is added across double bond and an alcohol is formed
34
What happens when alkenes react with halogens?
Molecules formed are saturated with C=C carbon each becoming bonded to a halogen atom
35
How to test for alkenes?
Add orange bromine water to a double bond
If alkene the alkene will make it colourless
36
What are polymers?
Long molecules formed when lots of small molecules called monomers join together
37
What is the formation of polymers known as?
Polymerisation - usually needs high pressure and catalyst
38
What are plastics made up of?
Polymers that are usually carbon based and their monomers often alkenes
39
What are addition polymers made up of?
- made from unsaturated monomers that have a double covalent bond
40
What is addition polymerisation?
Lots of unsaturated monomer molecules can open up their double bonds and join together to form polymer chains
41
General formula for alcohols?
CnH2n+1OH
42
First four alcohols in homologous series?
Methanol, ethanol, propanol, butanol
43
Properties of methanol, ethanol, propanol, butanol alcohols?
- flammable to produce carbon dioxide and water
- soluble in water
- oxidised by reacting with oxygen
44
Use of alcohols?
Solvents
Fuels
45
Process of fermentation?
Enzyme in yeast to convert sugars into ethanol as well as carbon dioxide
Happens fastest at 37c in a slightly acidic solution and under anaerobic conditions
46
Formula of fermentation?
Yeast
Sugar ————-> ethanol + carbon dioxide
47
Functional group of carboxylic acids?
- COOH
48
What are carboxylic acids?
Name ends in anoic acid
Homologous series of compounds
49
How do carboxylic acids react with carbonates?
Produce salt, water and carbon dioxide
Salts formed end in anoate
50
Formula for reaction carboxylic acid and carbonate?
Carboxylic acid + carbonate -> Salt + water + Carbon dioxide
51
How do carboxylic acids react with water?
- dissolve in water
- when dissolve, ionise it and release H+ ions resulting in acidic solution
52
How are esters formed?
From alcohol and carboxylic acids
53
Functional groups of esters?
COO
54
Formula for creation of esters?
Acid catalyst
Alcohol + carboxylic acid ————————-> ester + water
55
Process of condensation polymerisation?
- involves monomers which contain different functional groups
- Monomers react together and bonds form between them, making polymer chains
- for each new bond, a small molecule is lost
56
Names of first four carboxylic acids?
Methanoic, ethanoic, propanoic, butanoic
57
Differences in addition polymerisation and condensation polymerisation?
Number of types of monomers
Addition - only one monomer type containing C=C bond
Condensation- two monomer types containing two of same functional groups
Number of products
Addition - Only one product formed
Condensation- Two types the polymer and a small molecule
Functional groups involved in polymerisation
Addition - Carbon-carbon double bond in monomer
Condensation - two reactive groups on each monomer
58
What is amino acid made up of?
A basic amino group (NH2) and an acidic carboxylic group (COOH)
59
What do amino acids form via condensation polymerisation?
Polypeptides
60
What are one or more long chains of polypeptides known as?
Proteins
61
Structure of DNA?
Double helix
62
What is dna made up of?
Two polymer chains made up of monomers known as nucleotides
Bases on chains of polymer pair up with each other and form cross links keeping the two strands of nucleotides together
63
What do nucleotides contain?
Contain a small molecule known as the base
Order of bases acts as a code for an organisms genes
Bases - ‘A,C,G,T’
64
What are sugars?
Small molecules that contain carbon, oxygen and hydrogen
65
How do sugars react and what do they produce?
React together through polymerisation reactions to form larger carbohydrate polymers
