Considerable overlap with AS. Intermolecular forces are? Hydrogen bonding Hydrogen bonds operate...

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Considerable overlap with AS

Intermolecular forces are? Hydrogen bonding Hydrogen bonds operate between which

atoms? O(δ-) and H(δ+) Sketch diagram on page 1 of notes

End in -oic acid Other than that, pretty routine Examples: 2-chlorobutanoic acid, 4-hydroxypent-3-enoic acid 3,4-dichlorobenzenecarboxylic acid See questions on pages 2&3

Reaction with water produces hydroxonium ions

H3C CO

O

H+ H2O

ethanoic acid

H3C CO-

O+ H3O+

ethanoate

Reaction with a base produces a salt + water

Note NEVER show a bond (line) between Na+ and O-

H3C CO

O

H+ NaOH

ethanoic acid(carboxylic acid)

H3C CO-

O

+Na

sodium ethanoate(carboxylate salt)

+ H2O

Acid base Acid carbonate Acid metal See questions on page 4

As AS module Acid + alcohol ester + water Catalyst? Conc H2SO4

H2SO4C

O

O

H OC

O

O

+ H2OH

alcohol

carboxylicacid

molecule of water lost

new carbon-oxygen bond made

ester

Key

OH=

C

O

O=

H

ESTERIFICATION

C C

H

H O

OH

ethanoic acid

HC

methanol

H

H

O+ H2O

H +

CO

HC

H

H

O

methyl ethanoate

H

H2SO4C

H

H

H

carboxylic acid alcohol ester water

Can be carried out using acid or alkali Reagents/conds for hydrolysis; Dilute aqueous NaOH Dilute aqueous HCl

Acid conditions

H3C C

O

O

ethanoic acid

CH3OHH3C C

O

CH3O H

H2SO4

methyl ethanoate

HO

H

+

methanol

H3C C

O-

OCH3OH3C C

O

CH3O

H+ NaOH

sodium ethanoate

+Na

+

methyl ethanoate methanol

H2SO4

H3C C

O

O

H

(carboxylate salt)

ethanoic acid

Esters are used as food flavourings and perfumes.

Deduce the structure of the products of alkaline hydrolysis of the triglyceride on the previous slide.

Soap is formed

Depends whether the “tail” contains one or more double bonds

What do cis and trans mean? Give the displayed formula of the two forms of 1,2-dichloroethene

2,3-dichlorobut-2-ene 3-bromohex-3-ene

     Try this one: (numbers indicate positions of double bonds)

Cis-9-octadecenoic acid(Oleic acid) Trans-9-octadecenoic acid(Elaidic acid)

Trans-9-octadecenoic acid(Elaidic acid)

Octadecanoic acid 18,0 i.e. 18 C’s, no double bonds Octade-9-enoic acid, 18,1,(9) i.e. 18 C’s, 1 double bond at C No 9, (carbon

number 9 is the first forming a double bond) Octadec-9,12-dienoic acid 18,2,(9,12) etc

Saturated fats Bad Unsaturated fats Good Trans fats bad

A modified diesel engine can run on vegetable oil – “chip fat”

Vegetable oil and biodiesel are not the same

Methyl linoleate (linoleic acid = C18)

How would you convert “chip fat” into biodiesel