Rings, Acids And Amides

Front 1

Arene

Back 1

is an aromatic hydrocarbon contaning one or more benzene rings

Front 2

Aromatic

Back 2

is a compound that contains a bezene ring

Front 3

Benzene

Back 3

is a compound that contains 6 carbons and 6 hydrogens. empirical formula CH.
The structure is made by the electrons in the p-orbitals joining together to form a ring of delocalised electrons.
Thsi makes the structure stronger, and it can only take part in Electrophillc Substitution reactions.

Front 4

Halogenation

Back 4

Electrophillc reaction.
Br+ + C6H6 ---> C6H5Br + H+
Br+ is made from;
Br2 + FeBr3 --> Br+ +FeBr4-

The FeBr3 acts as a catalyst and is regenerated in the last stage

Front 5

Nitration

Back 5

Electrophillic reaction.
NO2+ + C6H6 --> C6H5NO2 +H+
NO2+ is made from;
H2SO4 + HNO3 --> NO2+ + HSO4- + H2O

The H2SO4 acts as a catalyst and is regenerated at the end.

Front 6

Cyclohexene

Back 6

Takes part in electrophilic addition reactions.
The bromine addds across the double bond.

C6H10 + Br2 --> C6H10Br2

Front 7

Phenols

Back 7

C6H5OH

Front 8

Phenol to form salts

Back 8

C6H5OH + NaOH --> C6H5O-Na+ + H2O

OR

2C6H5OH + 2Na --> 2C6H5O-Na+ + H2

Front 9

Phenol-Halogenation, and why it happens

Back 9

Electrophillic substitution

C6H5OH + 3Br2 --> C6H5OHBr3 (2,4,6-tribromophenol) + 3HBr

It's easy for phenol, as the extra electron in the delocalised ring, and it's easier to polarize bromine and all electrophiles

Front 10

Phenols - useage

Back 10

Phenols are used in a number of different ways;
antiseptics,
detergents
paints,
disinfectants

Front 11

Oxidation of primary alcohols

Back 11

forms an aldehyde and then under further oxidation forms a carboxylic acid.

H+/Cr2O7(2-)-oxidising agent
Agent made from K2Cr2O7 and H2SO4

Front 12

Oxidation of secondary alcohols

Back 12

forms a ketone

H+/Cr2O7(2-)-oxidising agent
Agent made from K2Cr2O7 and H2SO4

Front 13

Reduction of aldehydes

Back 13

Forms a primary alcohol.
Nucleophilic addition

Reducing agent NaBH4, under heat

Front 14

Reduction of Ketones

Back 14

Forms an aldehyde.
Nucleophilic addition

Reducing agent is NaBH4

Front 15

Reduction of Ketones

Back 15

Forms a secondary alcohol.
Nucelophilic addition

Reducing agent is NaBH4

Front 16

Carbonyl Tests

Back 16

Detect presence of aldehydes and ketones with 2,4-DNP (2,4-dinitrophenylhydrazine) (mixture of methanol and sulphuric acid)
a yellow orange precipitate is formed

Front 17

Alehyde or ketone

Back 17

Tollens reagent is used to distinguish between the two, by oxidising it.
Tollens reasgent is made by sodium hyrdoxide(aq) added to silver nitrate, till brown precipitate and then ammonia is added till the precipitate is dissolved
If an aldehyde is present then a silver mirror (a solid) will form.

Front 18

Identifying the carbonyl compound

Back 18

Purify the yello/worange precipitate, by filtering and then recyrstalising, then allow it to dry.
melting poin of this derivative is measured and then compared to a database, to identify the orginal compound

Front 19

Carboxylic acids - solubility

Back 19

Are soluble when small chanin lengths, as the chain increases the hydrogen bonds that form between the C=O and the O-H polar bonds are not stong enough to dissolve the acid

Front 20

Carboxylic acids - reactions with...

Back 20

...Metals;
Acid + Metal --> metal salt + hydrogen.

...Bases;
Acid + Base --> metal salt + water

...Carbonates;
Acid + Carbonate --> metal salt + carbon dioxide + water

Front 21

Esterification

Back 21

an ester is made from a carboxylic and and alcohol. The alcohol makes the, yl and the acid makes the oate.
Products are an ester and water.
With conc sulphuric as a catalyst.

OR

By heating an acid anhydride and an alcohol, the products are an ester and a carboxylic acid

Front 22

Ester Hydrolysis

Back 22

Two ways;

Acid;
reflux, dilute H2SO4-catalyst

Ester + water --> Carboxylic acids + alcohol

Alkaline;
Aqueous sodium hyrdoxied, reflux,
Ester + NaOH --> Sodium salt + Ethanol

Front 23

Esters - useage

Back 23

Esters are used in perfumes and flavouring, as they have such pleasent scents,

Front 24

Naming fats

Back 24

Short hand 18:2(9,12)
there are 18 carbons, 2 double bonds at the position 9 and 12.

Front 25

Triglyceride

Back 25

is a triester of glycerol and 3 fatty acids, with the fatty acids jkoined to the alcohol groups by ester linkages.

Front 26

Saturated and unsaturated

Back 26

Saturated fats contain no double bonds, and are worse for you in the body, as they increase the level of LDL's.
Unsaturated fats are better as they increase the level of HDL's.

Front 27

cis and trans

Back 27

Trans fats are very bad for you as they act the same as saturated fats. they pack closley together, so you get moremolecules in the same area

Front 28

Biodiesel

Back 28

scientists have developed biodiesels.
Made by transesterification.
triglycerides reacted with slcohol, with a sodium hydorxide catalyst. glycerol is also formed, and sold to phameceutical companies.

triglyceride + 3alcohol --> biodiesel + glycerol

Front 29

Amines

Back 29

Amines are derivative of ammonia, primary seconday and tertiary.
Naming them;
primary
carbons, 4, butyl.
suffix, amine.
butyl amine

secondary,
longest chain, propyl,
suffix, amine,
shortest chain, N-methyl
N-methylpropylamine


They are classed as bases as they accept protons, as nitrogen has a lone pair of electons. so they can form a dative covalent bond with a hydrogen ion.

Front 30

Amine - base reactions

Back 30

Amine + Acid --> Alkylamonium salt.

NH3+Cl- When reacted with HCl

NH3+NO3- when reacted with HNO3

Front 31

Aliphatic Amine

Back 31

warming halogenoalkane
excess of ammonia
ethanol as solvent

Halogonalkane + Ammonia --> Amine + Acid

Front 32

Aromatic

Back 32

Nitrobenzene is reduced using tin and conc HCl, under reflux,

Nitrobenzene + 6[H] --> Phenylamine +2H2O

Front 33

Azo dyes - diazotisation

Back 33

NaNO2 + HCl --> HNO3+ + NaCl
below 10degrees
Nitrobenzene + HNO3 + NCl --> Benzenediazonium chloride + 2H20

Front 34

Azo Dyes - Coupling

Back 34

Bezenediazonium + phenol + NaOH --> Azo dye + NaCl + H20