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CHXII12:ALDEHYDES KETONES AND CARBOXYLIC ACIDS

323398 Select the correct statement(s) for the following.

1 Nitriles are hydrolyzed to amides and then to acids in the presence of

H^{+}

or

{OH}^{-}

as catalyst.

2 Mild reaction conditions are used to stop the reaction at the amide stage during the hydrolysis of nitriles

3 Grignard reagents react with dry ice to form salts of carboxylic acids which in turn give corresponding carboxylic acids after acidification with mineral acid

4 All of the above

CHXII12:ALDEHYDES KETONES AND CARBOXYLIC ACIDS

323399 In which of the following compounds the methylenic hydrogens are the most acidic?

1

{CH}_{3} {COCH}_{2} {CH}_{3}

2

{CH}_{3} {CH}_{2} {COOC}_{2} H_{5}

3

{CH}_{3} {CH}_{2} CH {({COOC}_{2} H_{5})}_{2}

4

{CH}_{3} {COCH}_{2} CN

Explanation:

$E W G \propto$ Acidic strength

CHXII12:ALDEHYDES KETONES AND CARBOXYLIC ACIDS

323400 Acid hydrolysis of which of the following compounds yields two different organic compounds?

1

{CH}_{3} COOH

2

{CH}_{3} {CONH}_{2}

3

{CH}_{3} {COOC}_{2} H_{5}

4

{({CH}_{3} CO)}_{2} O

Explanation:

Acid hydrolysis of an ester gives two different organic compounds.
$C H_{3} COO C_{2} H_{5} + H_{2} O \to$
$\underset{Both organic compounds}{C H_{3} COOH} + C_{2} H_{5} OH$
Acid hydrolysis of a symmetrical anhydride gives two molecules of the same organic compound.
${({CH}_{2} CO)}_{2} O + H_{2} O \to 2 {CH}_{3} COOH$
While the acid hydrolysis of an amide gives one organic and one inorganic product as,
$C H_{3} CON H_{2} + H_{2} O \to$
$\underset{Organic compound}{C H_{3} COOH} + \underset{Inorganic compound}{N H_{3}}$

AIIMS - 2008

CHXII12:ALDEHYDES KETONES AND CARBOXYLIC ACIDS

323401 Order of hydrolysis for the following
I. $RCOCl$ II. RCOOR
III. ${RCONH}_{2}$ IV. ${(R C O)}_{2} O$

1 I

>

IV

>

II

>

III

2 I

>

II

>

III

>

IV

3 I

>

III

>

II

>

IV

4 IV

>

III

>

II

>

I

Explanation:

Acid chlorides are most reactive and are easily hydrolysed by water as follows
supporting img
Acid anhydrides are less reactive than acid chlorides.
They are hydrolysed slowly by water than acid chloride.

Esters are hydrolysed by water only in presence of acid or alkali.

Amides are hydrolysed by water in the presence of an acid

Hence, the correct order of hydrolysis is
$R C O C l > (R C O)_{2} O > R C O O R > R C O N H_{2}$

CHXII12:ALDEHYDES KETONES AND CARBOXYLIC ACIDS

323398 Select the correct statement(s) for the following.

1 Nitriles are hydrolyzed to amides and then to acids in the presence of

H^{+}

or

{OH}^{-}

as catalyst.

2 Mild reaction conditions are used to stop the reaction at the amide stage during the hydrolysis of nitriles

3 Grignard reagents react with dry ice to form salts of carboxylic acids which in turn give corresponding carboxylic acids after acidification with mineral acid

4 All of the above

CHXII12:ALDEHYDES KETONES AND CARBOXYLIC ACIDS

323399 In which of the following compounds the methylenic hydrogens are the most acidic?

1

{CH}_{3} {COCH}_{2} {CH}_{3}

2

{CH}_{3} {CH}_{2} {COOC}_{2} H_{5}

3

{CH}_{3} {CH}_{2} CH {({COOC}_{2} H_{5})}_{2}

4

{CH}_{3} {COCH}_{2} CN

Explanation:

$E W G \propto$ Acidic strength

CHXII12:ALDEHYDES KETONES AND CARBOXYLIC ACIDS

323400 Acid hydrolysis of which of the following compounds yields two different organic compounds?

1

{CH}_{3} COOH

2

{CH}_{3} {CONH}_{2}

3

{CH}_{3} {COOC}_{2} H_{5}

4

{({CH}_{3} CO)}_{2} O

Explanation:

Acid hydrolysis of an ester gives two different organic compounds.
$C H_{3} COO C_{2} H_{5} + H_{2} O \to$
$\underset{Both organic compounds}{C H_{3} COOH} + C_{2} H_{5} OH$
Acid hydrolysis of a symmetrical anhydride gives two molecules of the same organic compound.
${({CH}_{2} CO)}_{2} O + H_{2} O \to 2 {CH}_{3} COOH$
While the acid hydrolysis of an amide gives one organic and one inorganic product as,
$C H_{3} CON H_{2} + H_{2} O \to$
$\underset{Organic compound}{C H_{3} COOH} + \underset{Inorganic compound}{N H_{3}}$

AIIMS - 2008

CHXII12:ALDEHYDES KETONES AND CARBOXYLIC ACIDS

323401 Order of hydrolysis for the following
I. $RCOCl$ II. RCOOR
III. ${RCONH}_{2}$ IV. ${(R C O)}_{2} O$

1 I

>

IV

>

II

>

III

2 I

>

II

>

III

>

IV

3 I

>

III

>

II

>

IV

4 IV

>

III

>

II

>

I

Explanation:

Acid chlorides are most reactive and are easily hydrolysed by water as follows
supporting img
Acid anhydrides are less reactive than acid chlorides.
They are hydrolysed slowly by water than acid chloride.

Esters are hydrolysed by water only in presence of acid or alkali.

Amides are hydrolysed by water in the presence of an acid

Hence, the correct order of hydrolysis is
$R C O C l > (R C O)_{2} O > R C O O R > R C O N H_{2}$

CHXII12:ALDEHYDES KETONES AND CARBOXYLIC ACIDS

323398 Select the correct statement(s) for the following.

1 Nitriles are hydrolyzed to amides and then to acids in the presence of

H^{+}

or

{OH}^{-}

as catalyst.

2 Mild reaction conditions are used to stop the reaction at the amide stage during the hydrolysis of nitriles

3 Grignard reagents react with dry ice to form salts of carboxylic acids which in turn give corresponding carboxylic acids after acidification with mineral acid

4 All of the above

CHXII12:ALDEHYDES KETONES AND CARBOXYLIC ACIDS

323399 In which of the following compounds the methylenic hydrogens are the most acidic?

1

{CH}_{3} {COCH}_{2} {CH}_{3}

2

{CH}_{3} {CH}_{2} {COOC}_{2} H_{5}

3

{CH}_{3} {CH}_{2} CH {({COOC}_{2} H_{5})}_{2}

4

{CH}_{3} {COCH}_{2} CN

Explanation:

$E W G \propto$ Acidic strength

CHXII12:ALDEHYDES KETONES AND CARBOXYLIC ACIDS

323400 Acid hydrolysis of which of the following compounds yields two different organic compounds?

1

{CH}_{3} COOH

2

{CH}_{3} {CONH}_{2}

3

{CH}_{3} {COOC}_{2} H_{5}

4

{({CH}_{3} CO)}_{2} O

Explanation:

Acid hydrolysis of an ester gives two different organic compounds.
$C H_{3} COO C_{2} H_{5} + H_{2} O \to$
$\underset{Both organic compounds}{C H_{3} COOH} + C_{2} H_{5} OH$
Acid hydrolysis of a symmetrical anhydride gives two molecules of the same organic compound.
${({CH}_{2} CO)}_{2} O + H_{2} O \to 2 {CH}_{3} COOH$
While the acid hydrolysis of an amide gives one organic and one inorganic product as,
$C H_{3} CON H_{2} + H_{2} O \to$
$\underset{Organic compound}{C H_{3} COOH} + \underset{Inorganic compound}{N H_{3}}$

AIIMS - 2008

CHXII12:ALDEHYDES KETONES AND CARBOXYLIC ACIDS

323401 Order of hydrolysis for the following
I. $RCOCl$ II. RCOOR
III. ${RCONH}_{2}$ IV. ${(R C O)}_{2} O$

1 I

>

IV

>

II

>

III

2 I

>

II

>

III

>

IV

3 I

>

III

>

II

>

IV

4 IV

>

III

>

II

>

I

Explanation:

Acid chlorides are most reactive and are easily hydrolysed by water as follows
supporting img
Acid anhydrides are less reactive than acid chlorides.
They are hydrolysed slowly by water than acid chloride.

Esters are hydrolysed by water only in presence of acid or alkali.

Amides are hydrolysed by water in the presence of an acid

Hence, the correct order of hydrolysis is
$R C O C l > (R C O)_{2} O > R C O O R > R C O N H_{2}$

CHXII12:ALDEHYDES KETONES AND CARBOXYLIC ACIDS

323398 Select the correct statement(s) for the following.

1 Nitriles are hydrolyzed to amides and then to acids in the presence of

H^{+}

or

{OH}^{-}

as catalyst.

2 Mild reaction conditions are used to stop the reaction at the amide stage during the hydrolysis of nitriles

3 Grignard reagents react with dry ice to form salts of carboxylic acids which in turn give corresponding carboxylic acids after acidification with mineral acid

4 All of the above

CHXII12:ALDEHYDES KETONES AND CARBOXYLIC ACIDS

323399 In which of the following compounds the methylenic hydrogens are the most acidic?

1

{CH}_{3} {COCH}_{2} {CH}_{3}

2

{CH}_{3} {CH}_{2} {COOC}_{2} H_{5}

3

{CH}_{3} {CH}_{2} CH {({COOC}_{2} H_{5})}_{2}

4

{CH}_{3} {COCH}_{2} CN

Explanation:

$E W G \propto$ Acidic strength

CHXII12:ALDEHYDES KETONES AND CARBOXYLIC ACIDS

323400 Acid hydrolysis of which of the following compounds yields two different organic compounds?

1

{CH}_{3} COOH

2

{CH}_{3} {CONH}_{2}

3

{CH}_{3} {COOC}_{2} H_{5}

4

{({CH}_{3} CO)}_{2} O

Explanation:

Acid hydrolysis of an ester gives two different organic compounds.
$C H_{3} COO C_{2} H_{5} + H_{2} O \to$
$\underset{Both organic compounds}{C H_{3} COOH} + C_{2} H_{5} OH$
Acid hydrolysis of a symmetrical anhydride gives two molecules of the same organic compound.
${({CH}_{2} CO)}_{2} O + H_{2} O \to 2 {CH}_{3} COOH$
While the acid hydrolysis of an amide gives one organic and one inorganic product as,
$C H_{3} CON H_{2} + H_{2} O \to$
$\underset{Organic compound}{C H_{3} COOH} + \underset{Inorganic compound}{N H_{3}}$

AIIMS - 2008

CHXII12:ALDEHYDES KETONES AND CARBOXYLIC ACIDS

323401 Order of hydrolysis for the following
I. $RCOCl$ II. RCOOR
III. ${RCONH}_{2}$ IV. ${(R C O)}_{2} O$

1 I

>

IV

>

II

>

III

2 I

>

II

>

III

>

IV

3 I

>

III

>

II

>

IV

4 IV

>

III

>

II

>

I

Explanation:

Acid chlorides are most reactive and are easily hydrolysed by water as follows
supporting img
Acid anhydrides are less reactive than acid chlorides.
They are hydrolysed slowly by water than acid chloride.

Esters are hydrolysed by water only in presence of acid or alkali.

Amides are hydrolysed by water in the presence of an acid

Hence, the correct order of hydrolysis is
$R C O C l > (R C O)_{2} O > R C O O R > R C O N H_{2}$