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Chemistry
Carbonyl Compounds
1
...

Nomenclature of aldehydes:
In the trivial or common system, aldehydes are named after the carboxylic acids
they form an oxidation
...


E
...
,

HCHO (or)

H

H–C=O
Formaldehyde

(corresponding acid is formic acid)

H

CH3 – CHO (or) CH3 – C = O
Acetaldehyde
(corresponding acid is acetic acid)

In the IUPAC system, the ending of the name (suffix) of aldehyde is ‘al’
...

i
...
, Name of aldehyde = Name of corresponding alkane – e + al
E
...
, 1
...
e
...

–e

Methane

Methanal
+al
+ al

2
...
CH3 – CH2 – CHO (Propanal)
The common and IUPAC names of some aldehydes are given below
...


Common Name

IUPAC name

H – CHO

Formaldehyde

Methanal

CH3 – CHO

Acetaldehyde

Ethanal

CH3 – CH2 – CHO

Propionaldehyde

Propanal

CH3 – CH2 – CH2 – CHO

Butyraldehyde

Butanal

Write a brief account of nomenclature of ketones
...

For example,

CH3 – CO – CH2 – CH3
Ethyl methyl ketone

CH3 – CO – CH3
Dimethyl ketone or Acetone

In the IUPAC system, the characteristic ending for ketones is – ‘one’
...

‘e’ in the name of the corresponding alkane by the suffix – ‘one’
...
e
...


3
...

Rules of naming ketones in the IUPAC system
...
The longest chain containing the CO group is selected and the name of the
parent hydrocarbon is decided
...
The last ‘e’ of the name of the hydrocarbon is replaced by ‘one’
...
The number of C atoms in the chain is started from the end which is nearest to
the carbonyl group (C = O)
Example:
1

2

3

4

5

In the compound, CH3 – CO – CH2 – CH2 – CH3 there are five C atoms, so the
parent hydrocarbon is pentane and the name of the ketone is 2 – pentanone or pentan – 2
– one (the CO group gets number 2)
...


4
...

The simple carboxylic acids are better known by their common names
...

For example:
1
...

2
...

IUPAC system:
1
...

2
...

i
...
, Name of Carboxylic acid = Name of corresponding alkane – e + oic acid

Example:

1
...

–e

Methane

Methanoic acid

+ oic acid

2
...


Give common and IUPAC name for the following compounds
...


Common Name

IUPAC name

(a) CH3 – CO – CH2 – CH3

Ethyl methyl ketone

butanone

(b) CH3 – CH2 – CO – CH2 – CH3

Diethyl ketone

3 – butanone or pentan –3 – one

(c) CH3 – CH2 – COOH

Propionic acid

Propanoic acid

(d) HCOOH

Formic acid

Methanoic acid

Discuss the manufacture of acetic acid from pyroligeneous acid
...
The important ones are –
(i) wood gas
(ii) an aqueous distillate called pyroligneous acid
(pyro = fire, lignum = wood)
(iii) wood tar and
(iv) wood charcoal
Pyroligneous acid solution contains acetic acid (10%), methyl alcohol (4%) and
acetone (0
...
The vapours of pyroligneous acid are passed through hot milk of lime
...
Methyl alcohol, acetone

and water vapours pass off
...

These crystals are then treated with concentrated sulphuric acid to obtain acetic acid
...


CaSO4  + 2 CH3 COOH

Give any five uses of Ethanoic acid
...
as a coagulant for rubber latex
...
in the manufacture of plastics, rayon, drugs and silk
...
Dilute aqueous solution (3 – 7%) of ethanoic acid is called vinegar, which is used to
preserve food
...
Pure ethanoic acid is used as a solvent and chemical reagent
...
As cellulose ethanoate, it is used in making photographic films and rayon
...


Give any four chemical properties of acetic acid
...

Acetic acid can donate a proton and form salts with bases i
...
, this shows the acidic
nature of acetic acid
...
g
...
g
...



E
...
, CH3 COOH + NH3
Acetic acid

CH3 COONH4
Ammonium acetate

CH3 CONH2 + H2O
Acetamide

(iv) Formation of esters: Acetic acid reacts with ethyl alcohol in the presence of
a strong acid catalyst like H2SO4 to form esters
...


Example:
CH3 COOH + C2H5OH
Acetic acid

Ethyl alcohol

H+



CH3 COOC2H5

+

H2 O

Ethyl acetate



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