considerable overlap with as. intermolecular forces are? hydrogen bonding hydrogen bonds operate...
TRANSCRIPT
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
