Organic Chemistry

Front 1

Homologous Series

Back 1

-same general formula.

-They show a gradual change in physical properties (e.g. boiling point).

- Each member differs by CH2 from the last.

- same chemical properties.

Front 2

Homolytic Fission

Back 2

each atom gets one electron from the covalent bond

Front 3

E-Z stereoisomers arise when:

Back 3

-There is restricted rotation around the C=C double bond.

-There are two different groups/atoms attached both ends of the double bond.

Front 4

Fractional Distillation Tube (steps)

Back 4

Back (Definition)

Hint 4

The diagram

Front 5

Economic reasons for cracking

Back 5

The petroleum fractions with shorter C chains (e.g. petrol and naphtha) are in more demand than larger fractions.

• To make use of excess larger hydrocarbons and to supply demand for shorter ones, longer hydrocarbons are cracked.

• The products of cracking are more valuable than the starting materials (e.g. ethene used to make poly(ethene), branched alkanes for motor fuels, etc.)

Front 6

Thermal Cracking

Back 6

High pressure (7000 kPa)

High temperature (400°C to 900°C)

Produces mostly alkenes

Sometimes produces hydrogen

Front 7

Catalytic Cracking

Back 7

Slight or moderate pressure High temperature (450°C)

Zeolite catalyst

Produces branched and cyclic alkanes and aromatic hydrocarbons

Front 8

Environmental consequence of nitrogen oxides

Back 8

NO- toxic and can form acidic NO2

NO2- toxic and acidic and forms acid rain

Front 9

Environmental consequence of Carbon monoxide

Back 9

Toxic

Front 10

Environmental consequence of Carbon dioxide

Back 10

Contributes towards global warming

Front 11

Environmental consequence of unburnt hydrogens

Back 11

Contributes towards formation of smog

Front 12

Environmental consequence of soot

Back 12

Global dimming and respiratory problems

Front 13

What catalysts are used in catalyst converters?

Back 13

platinum, palladium, rhodium

Front 14

Free radical

Back 14

reactive species which possess an unpaired electron

Front 15

Steps of Free Radical Substitution

Back 15

Initiation

Propagation

Termination

Front 16

σ bonds and π bonds

Back 16

Back (Definition)

Front 17

Hydrolysis

Back 17

a reaction where the molecule is split by the addition of water

Front 18

Conditions for hydration of alkenes to form alcohols

Back 18

High temperature 300 to 600°C High pressure 70 atm

Catalyst of concentrated H3PO4

CH2=CH2 (g) + H2O (g)  CH3CH2OH (l)

Front 19

Distillation Set Up

Back 19

Back (Definition)

Front 20

Reaction: primary alcoholcarboxylic acid

Back 20

Reagent: potassium dichromate(VI) solution and dilute

sulfuric acid

Conditions: use an excess of dichromate, and heat under reflux: (distill off product after the reaction has finished)

Hint 20

Reagents and conditions

Front 21

Reaction: primary alcoholcarboxylic acid

Back 21

Reagent: potassium dichromate(VI) solution and dilute

sulfuric acid

Conditions: use an excess of dichromate, and heat under reflux: (distill off product after the reaction has finished)

Hint 21

Reagents and conditions

Front 22

Reaction: AlcoholAlkene

Back 22

Reagents: Concentrated sulfuric or phosphoric acids Conditions: warm (under reflux)

Role of reagent: dehydrating agent/catalyst

Type of reaction: acid catalysed elimination

Front 23

Fermentation

Back 23

glucoseethanol + carbon dioxide C6H12O6  2 CH3CH2OH + 2 CO2

The conditions needed are: •Yeast

•No air

•temperatures 30 –40oC

Front 24

Fermentation

Back 24

glucoseethanol + carbon dioxide C6H12O6  2 CH3CH2OH + 2 CO2

The conditions needed are: •Yeast

•No air

•temperatures 30 –40oC

Front 25

Advantages of Fermentation

Back 25

sugar is a renewable resource

•production uses low level technology / cheap equipment

Front 26

Disadvantages of Fermentation

Back 26

batch process which is slow and gives high production costs

•ethanol made is not pure and needs purifying by fractional distillation

•depletes land used for growing food crops

Front 27

Hydration of Ethene

Back 27

Reagent: ETHENE - from cracking of fractions from distilled crude oil

CH2=CH2 (g) + H2O (g) CH3CH2OH (l)

high temperature 300 °C

high pressure 70 atm

strong acidic catalyst of conc H3PO4

Front 28

Advantages of hydration of ethene

Back 28

faster reaction

•purer product

•continuous process (which means cheaper manpower)

Front 29

Disadvantages of hydration of ethene

Back 29

high technology equipment needed (expensive initial costs)

•ethene is non-renewable resource (will become more expensive when raw materials run out) •high energy costs for pumping to produce high pressures

Front 30

Stereoisomers

Back 30

have the same structural formulae but have a different spatial arrangement of atoms

Front 31

Formation of a racemate

Back 31

A racemate will be formed in a reaction mechanism when a reactant or intermediate has a trigonal planar group in the molecule is approached from both sides by an attacking species

Front 32

Catalytic Hydrogenation

Back 32

Reagent: hydrogen and nickel catalyst Conditions: high pressure

Front 33

Addition of hydrogen cyanide to carbonyls to form hydroxynitriles

Back 33

Reaction: carbonylhydroxynitrile

Reagent: sodium cyanide (NaCN) and dilute sulfuric acid.

Conditions: Room temperature and pressure Mechanism: nucleophilic addition

Front 34

How soap works

Back 34

Long chain carboxylic (fatty) acids, produced by the hydrolysis of fats, act as soaps. The polar CO2- end is hydrophilic and mixes with water. The long non-polar hydrocarbon chain is hydrophobic and mixes with grease. So this allows the grease and water to mix and be washed away.

Front 35

Biodiesel

Back 35

is a mixture of methyl esters of long chain carboxylic acids

Front 36

Advantages of hydration of ethene

(3 points on card)

Back 36

faster reaction

•purer product

•continuous process (which means cheaper manpower)

Front 37

Measuring melting point

Back 37

-If impurities are present (and this can include solvent from the recrystallisation process) the melting point will be lowered and the sample will melt over a range of several degrees Celsius

-comparing an experimentally determined melting point value with one quoted in a data source will verify the degree of purity

Front 38

Aliphatic

Back 38

Straight or branched chain organic substances

Front 39

Aromatic/Arene

Back 39

Includes one or more ring of six carbon atoms with delocalised bonding

Front 40

carcinogen

Back 40

Benzene is a carcinogen (cancers causing molecule) and is banned for use in schools.

Front 41

Equation for formation of electrophile for Nitration of Benzene

Back 41

HNO3 + 2H2SO4  NO2+ + 2HSO4- + H3O+

This is an acid base reaction. The HNO3 acts as a base

Front 42

Friedel Crafts Acylation

Back 42

Reagents: acyl chloride in the presence of anhydrous aluminium chloride catalyst

Conditions: heat under reflux (50OC)

Mechanism: Electrophilic substitution

Hint 42

Conditions

mechanism

reagents

Front 43

Reducing a nitroarene to aromatic amines

Back 43

Reagent: Sn and HCl or Fe and HCl Conditions: Heating

Mechanism: reduction

Front 44

Types of polymerisation

Back 44

Addition

Condensation

Front 45

Terylene

Back 45

Common polyester

Front 46

Nylon 6,6

Back 46

Common polyamide

Front 47

Kevlar

Back 47

Common polyamide

Front 48

Uses Terylene

Back 48

Clothing

Tire cords

Front 49

Uses of nylon 6,6

Back 49

Fibres for textiles

Carpet

Moulded parts

Front 50

Uses of Kevlar

Back 50

Bulletproof vests

Gloves

Jacket

Helmets

Front 51

Disposal of Polymers- Landfill

Back 51

The most common method of disposal of waste in UK

Many are now reaching capacity.

European regulations will mean councils are charged much more for using landfill.

Most polymers (polyalkenes) are non-biodegradable and take many years to break down.

Could use more biodegradable plastics, e.g. Polyamides and cellulose and starch based polymers to improve rates of decomposition

Front 52

Disposal of Polymers- Landfill

Back 52

The most common method of disposal of waste in UK

Many are now reaching capacity.

European regulations will mean councils are charged much more for using landfill.

Most polymers (polyalkenes) are non-biodegradable and take many years to break down.

Could use more biodegradable plastics, e.g. Polyamides and cellulose and starch based polymers to improve rates of decomposition

Front 53

Disposal of Polymers- Incineration

Back 53

Rubbish is burnt and energy produced is used to generate electricity.

Some toxins can be released on incineration. Modern incinerators can burn more efficiently and most toxins and pollutants can be removed. Greenhouse gases will still be emitted though.

Volume of rubbish is greatly reduced.

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Disposal of Polymers- Recycling

Back 54

Saves raw materials- nearly all polymers are formed from compounds sourced/produced from crude oil. Saves precious resources.

Polymers need collecting/ sorting- expensive process in terms of energy and manpower.

Polymers can only be recycled into the same type – so careful separation needs to be done.

Thermoplastic polymers can be melted down and reshaped

Front 55

Thin-layer chromatography

Back 55

a) Wearing gloves, draw a pencil line 1 cm above the bottom of a TLC plate and mark spots for each sample, equally spaced along line.

b) Use a capillary tube to add a tiny drop of each solution to a different spot and allow the plate to air dry.

c) Add solvent to a chamber or large beaker with a lid so that is no more than 1cm in depth

d) Place the TLC plate into the chamber, making sure that the level of the solvent is below the pencil line. Replace the lid to get a tight seal.

e) When the level of the solvent reaches about 1 cm from the top of the plate, remove the plate and mark the solvent level with a pencil. Allow the plate to dry in the fume cupboard.

f) Spray paper with ninhydrin and put in oven Draw around them lightly in pencil.

g) Calculate the Rf values of the observed spots

Front 56

Tips for TLC

Back 56

Wear plastic gloves to prevent contamination from the hands to the plate

pencil line –will not dissolve in the solvent tiny drop – too big a drop will cause different

spots to merge

Depth of solvent– if the solvent is too deep it will dissolve the sample spots from the plate

lid– to prevent evaporation of toxic solvent

Will get more accurate results if the solvent is allowed to rise to near the top of the plate but the Rf value can be calculated if the solvent front does not reach the top of the plate

dry in a fume cupboard as the solvent is toxic

If ninhydrin is sprayed on an amino acid and then heated for 10 minutes then red to blue spots appear.

This is done because amino acids are transparent and cannot be seen.

Front 57

Nucleotides

Back 57

Back (Definition)

Front 58

Cisplatin

Back 58

The Pt(II) complex cisplatin is used as an anticancer drug.

The cisplatin version only works as two chloride ions are displaced and the molecule joins on to the DNA. In doing this it stops the replication of cancerous cells.

Cisplatin prevents DNA replication in cancer cells by a ligand replacement reaction with DNA in which a dative covalent bond is formed between platinum and a nitrogen atom on guanine.

Front 59

Equation for Formation of the electrophile in freidel crafts

Back 59

AlCl3 + CH3COCl  CH3CO+ AlCl4-

Front 60

Reasons TMS is used

Back 60

•its signal is away from all the others

•it only gives one signal

•it is non-toxic

•it is inert

•it has a low boiling point and so can be removed from sample easily

Front 61

Types of chromatography

Back 61

• thin-layer chromatography (TLC) – a plate is coated

with a solid and a solvent moves up the plate

• column chromatography (CC) – a column is packed

with a solid and a solvent moves down the column

• gas chromatography (GC) – a column is packed with a

solid or with a solid coated by a liquid, and a gas is passed through the column under pressure at high temperature.

Front 62

How stationary phase works in Chromatography

Back 62

A solid stationary phase separates by adsorption,

A liquid stationary phase separates by relative solubility

Front 63

Simple column chromatography

Back 63

•A glass tube is filled with the stationary phase usually silica or alumina in powder form to increase the surface area.

• A filter or plug is used to retain the solid in the tube. Solvent is added to cover all the powder.

• The mixture to be analysed is dissolved in a minimum of a solvent and added to the column.

• A solvent or mixture of solvents is then run through the column.

• The time for each component in the mixture to reach the end of the column is recorded (retention time)

Front 64

Why is Gas-Liquid Chromatography used?

Back 64

To separate mixture of volatile liquids

Area under peak is proportional to abundance

Time taken to leave is retention time

- used forensics, environment analysis, airport security and space probes

Front 65

What is the reducing agent used to reduce aldehydes/Ketones to alcohols

Back 65

NaBH4

Front 66

How is Biodiesel produced

Back 66

by reacting vegetable oils with methanol in the presence of a catalyst

Front 67

Condensation Polymers are formed by reacting between:

Back 67

-Dicarboxylic acid and diols

-Dicarboxylic acids and diamines

-Amino acids

Front 68

Test for acyl Chloride

Back 68

-water

Steamy/white fumes

-Aqueous silver nitrate

white precipitate (immediately formed)

-NaOH followed by acidified silver nitrate

white precipitate (immediately formed)

-Na2CO3 or NaHCO3

Fizzing or effervescence (not just gas produced)

-ammonia

White smoke

Front 69

Why are salts preferred in medicine?

Back 69

Salts Ionic

Soluble

Front 70

Observations for ketone and I2/NaOH

Back 70

Yellow ppt

Front 71

Industrial advantages for ethanoic anhydride than ethanoylic chloride

Back 71

less corrosive

less vulnerable to hydrolysis

less dangerous to use,

less violent /exothermic/vigorous reaction OR more controllable

does not produce toxic/corrosive/harmful fumes (of HCl) OR

does not produce HCl

less volatile

Front 72

Peak Shapes

Back 72

Back (Definition)

Front 73

Why does NMR use deuterated?

Back 73

1- To avoid swapping by the solvent

2- To stabilise the magnetic field strength

3- To accurately define 0ppm