F324

Front 1

Evidence Benzene has a delocalised structure

Back 1

1) Benzene all lengths are the of the single C-C bond and the double C=C bond is the same.

2) Hydrogenation of benzene is less exothermic than expected when compared to the kekule structure. As benzene is more thermodynamically stable.

3)Benzene is resistant to electrophilic attack.

Goes under electrophilic substitution not addition.

Front 2

Nitration of benzene

Back 2

*Reagents: Concentrated HNO3 and H2SO4

*Conditions: 55 Celsius

*Electrophile generation:

HNO3 + H2SO4 ----> NO2+ +HSO4- + H2O

*Regeneration of catalyst:

H+ +HSO4- ------> H2SO4

Front 3

Halogenation of benzene

Back 3

*Reagents: Cl2 / Br2 / I2 with (e.g) FeCl3/AlCl3

*Conditions: room temp & pressure

*Electrophile generation:

Cl2 + FeCl3 ----> FeCl4- + Cl+

*Regeneration of catalyst:

H+ + FeCl4- ------> FeCl3 + HCl

Front 4

Bromination of Phenol

Back 4

- Observation: Orange to Colorless and White precipitate.

- 3Br2 is needed and Br is attached to 2,4,6 position on the ring. + 3HBr

Front 5

Uses of Phenol

Back 5

1) Disinfectants

2) Production of plastic

3) Antiseptics

Front 6

Comparing Bromination of Cyclohexene, Benzene and Phenol

Back 6

[Benzene] Electrons are delocalised, this gives Benzene a lower electron density so it cannot polarise Br2 unless there is a halogen carrier.

[Cyclohexene] have ㅈ electrons that are localised, giving a higher electron density to polarise Br2

[Phenol] A lone pair of electrons from the oxygen is partially delocalised into the ring, it has a higher electron density so it can polarise Br2

Front 7

In Carbonyls why C=O bond does not react with electrophiles.

Back 7

The C=O is polarised as O is more electronegative than C. The ㅈ bond is unavailable to this polarisation. So electrophiles are repelled but nuclephiles are attracted to delta + Carbon.

Front 8

Reduction of Carbonyl Compounds

Back 8

* Type of reaction : Nucleophilic addition

* Reagent: NaBH4

* Conditions: Aqueous

* Nucleophile: H-

2[H] needed for every reducing

Front 9

Dectecting Carbonyl Compounds

Back 9

* Use 2,4 -DNPH

* Observation: Orange precipitate

1) Filter and recrystallize the ppt

2) Measure melting point of ppt

3) Measure against a known vaule.

Front 10

Distinguishing between Aldehydes and Ketones.

Back 10

* Use: Tollen's Reagent [Ag(NH3)2]+

* Aldehydes = Silver mirror is formed

Ag+ (aq) + e- -------> Ag (s)

RCHO (l) + [O] -------> RCOOH (l)

* Ketones = No reaction

Front 11

Solubility of C.ACIDS & Esters.

Back 11

Acids are soluble in organic solvents, as they can form hydrogen bonding. As mass increases, the solubility decreases.

Front 12

Uses of esters.

Back 12

1) Flavours

2) Perfume

3) Solvents

Front 13

Alcohol + Carboxylic Acid

Back 13

=Ester

Concentrated H2SO4.

Heat under reflux,

Front 14

Acid anhyrides & alcohols / phenol

Back 14

= Ester

Conditions: Gently Warm

Front 15

Hydrolysis of Esters

Back 15

1) Hot dilute aqueous HCl

2) Hot aqueous NaOH

Front 16

Glycerol / Propane-1,2,3-triol

Back 16

draw

Front 17

Fatty acids - Saturated / Unsaturated

Back 17

* Saturated straight chain. Can pack closely together, many points of contact + inter molecular forces = solid at rtp. BAD.

* Mono-nsaturated: one C=C bond, liquids at rtp.

* Trans fatty acids may increase cholesterol leading to increased risk of corony heart disease and strokes.

Front 18

Making Biodiesel

Back 18

Triglyceride + 3Alcohol -------> 3Biodiesel + glycerol.

* Conditions : NaOH catalyst + heat

* Alcohol is added in excess to shift the equilibrium to the right

* Methanol or ethanol is suitable alcohol.

Front 19

Formation of amine

Back 19

*Reagents: Excess Ethanolic Ammonia

(In excess to prevet further subsitution) & (Ethanol is a weaker nucleophile than water, excellent solvent)

*Conditions: Heat under reflux

*Nucleophile: NH3

CH3CH2Cl + 2NH3 ----> CH3CH2NH2 +NH4CL

*Type of reaction: Nucleophilic substitution

Front 20

C6H5NO2 + 6[H] -------> C6H5NH2 + 2H20

Reduction of Nitrobenzene

Back 20

* Reagents: Tin & Concentrated HCL.

* Conditions: Heat Under Reflux.

* Type of reaction: Reduction 6[H] for every NO2 & 2 H2O

Front 21

Azo dye sythesis. (Formation of diazonium salt)

Back 21

* Reagents: HNO2 + HCL

* Conditions: below 10 Celsius

Front 22

Coupling with phenols.

Back 22

* Reagents:Phenol + NaOH

* Conditions: Alkaline, below 10 Celsius

Use: dyes

Front 23

What modern day technology has disproved kekule's theory.

Back 23

X-ray diffraction, it showed all the benzene lengths are the same

Front 24

Alkylation

Back 24

Benzene + RCl -----> C6H5R + HCl

Front 25

a-amino acid definition

Back 25

The -NH2 and the -COOH group is attached to the same carbon atom

Front 26

Amino acid general formula

Back 26

RCH(NH2)COOH

Front 27

Zwitterion definition

Back 27

An ion that has both a positive and a negative charge

Front 28

Isoelectric point definition

Back 28

The pH at which the zwitterion exsits

Front 29

Isoelectric point which group exists

Back 29

1) More alkaline (pH increased) O-

2) More acidic (pH decreased) NH3+

Front 30

Z

Back 30

CIS (on same side)

Front 31

E

Back 31

Trans (on different sides)

Front 32

ACID Hydrolysis of peptides

Back 32

*Conditions : Hot Aqueous HCL, under reflux

NH3+

Front 33

ALKALINE Hydrolysis of peptides

Back 33

*Conditions : Hot Aqueous NaOH, under reflux

O-Na+

Front 34

Optical isomers

Back 34

Non-superimposable mirror images with 4 different groups attached to the central chiral carbon atom.

Each chiral carbon gives 2 non-superimposable mirror images.

Front 35

Condensation polymerisation

Back 35

Two different monomers that join together and a small molecule is given off as a side product such as H20 or HCL

Front 36

Addition polymerisation

Back 36

2 or more monomers join together to form a polymer, no other product is formed

Front 37

Hydrolysis of polymers

Back 37

1) C=O bond in condensation polymers make it photodegradable

2) Mirco-organisms can break it down (biodegradable)

3) ester or amide links can be hydrolysed

Front 38

Absorbption (Solid stationary phase)

Back 38

Solids are held on the stationary phase depending on the differences in polarity

Front 39

Relative solubility (Liquid stationary phase)

Back 39

Solutes more between stationary phase and mobile phase, based on how much they dissolve.

Front 40

Rf

Back 40

distance travelled by solute (y)

--------------------------------------------------(divide)

distance travelled by solvent (x)

Front 41

Nylon-6,6

Back 41

Front 42

Kevlar

Back 42

Front 43

Nylon-6,6 (using acyl chlorides)

Back 43

Front 44

Retention time

Back 44

Time taken from injection to dectection.

• Retention time depends on:

1) boiling point (high = long)

2) solubility in the liquid phase (greater = long)

Front 45

HNMR region on the electromagnetic spectrum

Back 45

Low energy radiowaves

Front 46

Ad/dis of sythesis single optical isomer

Back 46

1) side effects are eliminated

2) improves pharmlogical activity.

•Done by using enzymes or bacteria to promote steroselectivity.

•Natural chiral molecules.

Front 47

Chromatography

Back 47

Front 48

TLC

Back 48

Front 49

TLC

Back 49