for - isca.co.in

FOR

B.Tech,

CHEMICAL AND PETROCHEMICAL ENGINEERING STUDENTS

VOLUME 1

by

Ms. G. Sridevi Ms. R. Angayarkanni

Assistant Professor, Assistant Professor,

Department of Chemistry, Department of Chemistry,

Sriram Engineering College, Sriram Engineering College,

Tiruvallur, Tamilnadu, India. Tiruvallur, Tamilnadu, India.

E.Mail: [email protected] E.Mail:[email protected]

Ms. D. Mohanambal Mr. P. S. Syed Ibrahim

Assistant Professor, Assistant Professor,

Department of Chemistry, Department of Chemistry,

Sriram Engineering College, Sriram Engineering College,

Tiruvallur, Tamilnadu, India. Tiruvallur, Tamilnadu, India.

E.Mail: [email protected] E.Mail:[email protected]

2018

Ideal International E – Publication Pvt. Ltd. www.isca.co.in

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E-mail: [email protected] , Website: www.isca.co.in

Title: Organic Chemistry Lab Manual

Author(s): Ms. G. Sridevi, Ms. R. Angayarkanni, Ms. D. Mohanambal, Mr. P. S.

Syed Ibrahim

Edition: First

Volume: I

© Copyright Reserved

2018

All rights reserved. No part of this publication may be reproduced, stored, in a

retrieval system or transmitted, in any form or by any means, electronic,

mechanical, photocopying, reordering or otherwise, without the prior

permission of the publisher.

ISBN: 978-93-86675-51-4

Organic Chemistry Lab Manual iii

Ideal International E- Publication

www.isca.co.in

AUTHOR PREFACE

Chemistry is a very important discipline for understanding the nature. As a sub

discipline, organic chemistry is the study on the structures, properties, reactions and

preparations of hydrocarbons. Organic chemistry is the basis for related industries such as

fine chemicals, pharmaceuticals, biotechnology, etc. In the efforts to promote the

development of science and technology, and social progress, improve the quality of life and

preserve the environment, organic chemistry has shown and will continue to show great

potential. For many students, this realization foments a desire to pursue a career in one of the

various fields related to the discovery, study, or appropriate administration of medicines. In

our own case, this meant embarking on the study of organic chemistry and learning how to

synthesize organic molecules in the laboratory.

The idea of writing this book is to understand the fundamental concepts in the

preparation of organic compounds and the functional group present in different organic

compounds. This organic chemistry laboratory manual is also providing students to

understand real scientific knowledge of chemistry. The lab manual gives complete guidance

to both the lab instructor and the student.

We hope that this book will help the students develop a new perspective about the

usage and the safe handling of chemicals and apparatus used in the Chemistry laboratories

and make them more lab safety conscious. We wish our students a safer and a more enjoyable

Chemistry Lab experience.

Ms. G. SRIDEVI

Ms. R. ANGAYARKANNI

Ms. D. MOHANAMBAL

Mr. P. S. SYED IBRAHIM

Organic Chemistry Lab Manual iv


www.isca.co.in

ACKNOWLEDGEMENT

First and foremost, we would like to thank our college management,

Dr. G. Gopalakrishnan, Director (Academics), Sriram Engineering College, Perumalpattu and

Dr. S. R. Kannan, Principal, Sriram Engineering College, Perumalpattu for their

encouragements. We wish to extend our thanks to our family members and friends.

Ms. G. SRIDEVI

Ms. R. ANGAYARKANNI

Ms. D. MOHANAMBAL

Mr. P. S. SYED IBRAHIM

Organic Chemistry Lab Manual v


www.isca.co.in

CONTENTS

S.NO SECTION PAGE NO

A

1

2

GENERAL INSTRUCTIONS

LABORATORY PROCEDURES

SAFETY IN THE LABORATORY

1

2

B

1

2

3

4

5

PREPARATION OF ORGANIC COMPOUNDS

ACETYLATION – PREPARATION OF ACETANILIDE FROM

ANILINE.

HYDROLYSIS – PREPARATION OF SALYCILIC ACID FROM

METHYL SALYCILIATE.

SUBSTITUTION – CONVERSION OF ACETONE TO

IODOFORM.

NITRATION – PREPARATION OF M-DINITROBENZE FROM

NITROBENZENE.

OXIDATION – PREPARATION OF BENZOIC ACID FROM

BENZALDEHYDE

3

4

6

7

8

C

1

2

METHODOLOGY OF FILTERATION AND

RECRYSTALLISATION

METHODS OF FILTERATION

METHODS OF RECRYSTALATION

9

D ANALYSIS OF PROTEINS 11

E ANALYSIS OF CARBOHYDRATES 13

F

1

2

IDENTIFICATION OF SIMPLE ORGANIC COMPOUNDS

QUALITATIVE ANALYSIS OF ORGANIC COMPOUNDS

PREPARATION OF DERIVATIVES

17

33

Organic Chemistry Lab Manual 1

1

A.GENERAL INSTRUCTIONS

1. LABORATORY PROCEDURES

LABORATORY NOTEBOOK

Students should have an observation note that used in the lab for recording all

experimental data. A title should appear at the top of the page for each new experiment. Data

obtained during an experiment should always be neatly and clearly recorded in the

observation note.

PRE-LABORATORY PREPARATION

In order to prepare for the experiment, students are expected to read the appropriate

laboratory experiment prior coming to the lab. Students may be tested at the beginning of the

lab period to ensure they are prepared to begin work. The lab instructor also may require

students to answer pre-laboratory questions in the lab notebook.

LAB REPORTS

Before leaving the laboratory, each student must submit a laboratory datasheet as

described above. Lab reports can only be submitted for labs that have been attended and must

be submitted at the beginning of the lab session following the lab that is being reported.


2

2. SAFETY IN THE LABORATORY

Wear apron (lab overall) in the lab when running apparatus and handling liquids.

Find out the location of First Aid Box

Report all injuries to instructor immediately.

Avoid inhalation of gases or vapors.

Practice good housekeeping. Clean all spills at once. Return all equipment for proper

storage when not in use.

Know the location and use of all emergency, protective and firefighting equipment.

Do not smell directly any chemical being heated.

Remember that, if a lab smells, do not use it. Inform instructor/lab technician.

Do not leave lab while apparatus is on, always inform instructor if you are in a

situation to leave the lab.

Report to the instructor any conditions that are safety hazards.

Keep the lab tidy.

Always remember SAFTY IS GOOD TECHNIQUE!


3

B. PREPARATION OF ORGANIC COMPOUNDS

1. ACETYLATION – PREPARATION OF ACETANILIDE FROM ANILINE

Principle: Aniline is refluxed with glacial acetic acid in the presence of fused sodium acetate

when acetalinide is obtained.

Requirements:

1. Freshly distilled Aniline-------------------- 5ml

2. Glacial Acetic acid--------------------------- 6ml

3. Freshly Fused Sodium Acetate---------- 2gm

Procedure:

5ml of aniline, 6 ml of glacial acetic acid and 2gm of fused sodium acetate are taken in a

round bottom flask. The mouth of the flask is fitted with a long condenser and gently refluxed

by heating on wire gauze. The mixture is poured while hot into 100 ml of cold water

contained in a beaker with vigorous stirring. It is cooled and filtered at the pump. The slightly

colored substance is dissolved in about 150ml of boiling water, heated with 1gm animal

charcoal and filtered through a hot water funnel. The filtrate is allowed to cool. The

precipitate acetanilide is filtered, washed with a small quantity of water and dried. The yield

and the melting point are noted.

Result:

1. The yield of acetanilide = ………………g

2. Melting point of acetanilide = ……………....˚C

C6H5NH2+CH3COOH C6H5NH-COCH3 + H2O

(Aniline) (Acetic Acid) (Acetanilide)


4

2. HYDROLYSIS – PREPARATION OF SALICYCLIC ACID FROM

METHYL SALICYLATE

Principle:

Esters can be hydrolysed into their carboxylic acids either in acidic or basic medium

under refluxing condition .In this experiment methyl salicylate, an ester is refluxed with

aqueous base. Due to the presence of base, the carboxylic acid and phenolic –OH groups of

salicylic acid are ionized and give sodium salicylate. The reaction mixture is subsequently

acidified using sulphuric acid which converts this anion into the fully protonated acid i.e.,

Salicylic acid. The salicylic acid formed is filtered on a suction pump and purified by

crystallization.

OH O

OCH3

+ 2NaOH

ONa+

COONa+

+ CH3OH + H2O

H2SO4

OH

OH

O

Salicylic acid

Methyl Salicylate (dilute)

Requirements:

1. Methyl salicylate -----------3ml

2. Sodium Hydroxide 20%---20ml

Procedure:

The methyl salicylate is taken in a 250 ml round bottom flask fitted with liebig condenser

and NaOH solution is added in one lot. A few pieces of porcelain bits are added. The flask is

heated over wire guaze and the contents are refluxed until the oily layer of the ester has


5

completely disappeared. The contents of the flask are cooled and transferred to a beaker. The

solution is then acidified with conc.HCl with constant stirring. Crystals of salicyclic acid

separate. The beaker is cooled well and the crystals are filtered, washed with cold water and

dried. The yield is noted. A portion of it is recrystallized from boiling water.

Result:

1. The yield of salicylic acid = …………………..g

2. Melting point of salicylic acid = ……………………˚C


6

3. SUBSTITUTION –CONVERSION OF ACETONE TO IODOFORM

Principle:

Iodoform is prepared by the joint action of iodine and alkali upon acetone.

CH3COCH3+3I2 CI3-CO-CH3

CI3-CO-CH3 CHI3+CH3COONa

Requirements:

1. Acetone ---------------5ml

2. Sodium carbonate-----5gm

3. Powdered iodine------5gm

Procedure:

The sodium carbonate is dissolved in 20ml of water contained in a 100ml conical

flask. Acetone is added to the solution. The powdered iodine is then added in small quantities

at a time with stirring. The mixture is gradually warmed on a water bath to 70 to 80ºC for

about 15 minutes. On cooling, the iodoform separates as yellow crystals and is collected by

filtration. The product is washed with water, recrystallized from alcohol and dried. The yield

and melting point are noted.

Result:

1. Mass of Iodoform obtained = ……………….g

2. Melting point of Iodoform = ………………..˚C


7

4. NITRATION- PREPARATION OF M-DINITRO BENZENE

Principle:

m- Dinitrobenzene is prepared by the nitration of nitro benzene. The nitration is effected

by fuming nitric acid in presence of concentrated sulphuric acid.

NO2

+ HNO3

H2SO4

Heat

NO2

NO2

Nitrobenzene m-Dinitrobenzene

Requirements:

1. Nitrobenzene-------------------- 3ml

2. Fuming nitric acid-------------- 7ml

3. Concentrated Sulphuric acid---10ml

Procedure:

7ml of fuming nitric acid is taken in an R.B flask and 10ml of concentrated

Sulphuric acid is added, a little at a time cooling the flask during the addition.1ml of

nitrobenzene is then added in small quantities at a time to the nitrating mixture, shaking well

after each addition. Finally it is heated for about 45 minutes by immersion in a boiling water

bath, till a small quantity of the reaction mixture when added to a small quantity of water in a

test tube gives a solid immediately. The contents of the flask are then poured in fine stream

while still hot into 100ml of water contained in a beaker. The mixture is shaken very

vigorously during the addition. m- Dinitrobenzene separates as a solid which is filtered at the

pump washed several times with water, dried and the yield is noted. A small portion is

recrystallised from alcohol and the melting point is determined.

Result:

1. The yield of m-dinitrobenzene = …………….g

2. Melting point of m-dinitrobenzene = ……………..˚C


8

5. PREPARATION OF BENZOIC ACID FROM BENZALDEHYDE

Principle:

When benzaldehyde is oxidized using alkaline KMnO4 solution, benzoic acid is formed in the

form of its salt. The precipitated manganese dioxide is dissolved using acidified sodium

sulphite solution. Benzoic acid is then precipitated on acidifying the resulting solution using

conc.HCl.

1. Alk.KMnO4

C6H5CHO C6H5COOH

2. Con. HCl

Requirements:

Benzaldehyde --------------------- 3ml

Alk.KMnO4 ---------------------- 5ml

Sodium Sulphite ------------------ 5gm

Con. HCl --------------------------- 5ml

Procedure:

Benzaldehyde is mixed with aqueous sodium carbonate solution taken in a round

bottom flask. A bit of broken porcelain is added and the R. B. flask is fitted with a reflux

condenser. The contents are gently boiled by heating over a burner. An aqueous solution of

KMnO4 (prepared by dissolving 5g of KMnO4 in minimum amount of distilled water) is

added to the flask from top of the condenser in small quantity at a time until the solution

remains slightly pink. The flask is gently during the addition of KMnO4. Heating is continued

for about 30 minutes. Benzaldehyde is oxidized to benzoic acid and MnO2 is precipitated.

When the reaction is complete, the smell of benzaldehyde disappears.

The flask is cold and the contents are transferred into 250ml beaker. A std. Solution

of acidified sodium sulphite (5g in 20ml dil. H2SO4) is added with constant stirring until all

the precipitated MnO2 is dissolved. Then, to liberate the free acid con. HCl is added till the

precipitation is complete. Precipitated acid is filtered off, wash with water, dried using filter

paper and the yield is noted.

Result

The yield of benzoic acid is .....................g

Melting point of benzoic acid ...................˚C


9

C. METHODOLOGY OF FILTERATION AND RECRYSTALLISATION

FILTERATIONS

GRAVITY FILTERATION

Gravity filtration is the method of choice to remove solid impurities form an organic

liquid. The “impurity “can be a drying agent or an undesired side product or left over

reactant. Gravity filtration can be used to collect solid product, although generally vacuum

filtration is used for this purpose because it is faster.

A filtration procedure called “hot gravity filtration” is used to separate insoluble

impurities from a hot solution. Hot filtrations require fluted filter paper and careful attention

to the procedure to keep the apparatus warm but covered so that solvent does not evaporate.

SUCTION FILTRATION

Crystals may be collect6ed from a solution by filtration on a Buchner funnel. A partial

vacuum is created in the filter flask by a water aspirator. (Water flowing past a small hole in a

pipe draws in gas from the hose to the filter flask. this reduces the pressure creating the

partial vacuum. additional information on the operation of an aspirator can be obtained by

checking a physics textbook under “Bernoulli’s principle.”) The filter paper should be placed

in the funnel and wetted before starting the filtration to help seal it to the funnel. Ensure that

the filter flask is clamped to the retort stand and their rubber stopper holding the buchner

funnel is tight in the filtration flask.

Turn on the water to the aspirator to create a reduced pressure in the filtration flask.

Transfer the solution and the crystals in to the funnel-be careful not to overflow the funnel.

Swirl the last of the solution in the flask to help transfer any remaining crystals into the

funnel. Use a spatula to transfer crystals that are missed. Wash the crystals as instructed in the

lab manual and then compact the crystals with a spatula to push out as much solvent as

possible. Leave the crystals on the Buchner funnel with aspirator running to further dry the

crystals. Check the lab manual for any drying instructions.

RECRYSTALLISATION

The organic compounds are purified by recrystallisation form a suitable solvent which

can dissolve a large quantity of the substance at high temperature and deposit the same when

cooled.


10

A nearly saturated solution of the impure substance is prepared in a hot solvent. It is

decolorized with animal charcoal and filtered while hot. The filtrate on cooling deposits

crystals of the pure substance.

Recrystallisation of m-dinitrobenzene

About 1g of crude m-dinitrobenzene is recrystallized from hot rectified spirit.

Recrystallisation of Acetanilide

About 1g of crude acetanilide sample is dissolved in minimum amount of hot water,

1g of animal charcoal is added and then heated. The hot liquid is rapidly filtered. The filtrate

is allowed to cool. Acetanilide crystallizes out in rhombic plates.

Recrystallisation of Benzoic acid

About 0.5g of crude benzoic acid is dissolved in 5ml of boiling water, filtered poured

into a watch glass and allowed to cool slowly. After the crystals are formed, the liquid is

poured off and the crystals are dried with bits of filter paper.

RESULT:

1. Amount of recrystallised m-dinitrobenzene = ------g

2. Amount of recrystallised acetanilide = ------g

3. Amount of recrystallised benzoic acid = ------g


11

D. ANALYSIS OF PROTEINS

Protein can be analyzed by the following tests.

S.NO EXPERIMENT OBSERVATION INFERENCE

1 Biuret Test:

To a little amount of the substance

is treated with small amount of

NaOH solution and a dilute

solution of cupric sulphate is added

drop by drop.

This test used to detect the

presence of peptide bond

Bluish violet colour is

produced

Presence of protein

2 Xanthoproteic test:

To a little of the substance is

treated with con.HNO3

Yellow color is formed

due to xanthoproteic

acid. It turns orange if it

is made basic

Presence of protein

with amino acid

carrying aromatic

group

3 Ninhydrin Test:

The small amount of the substance

is treated with ninyhydrin

Intense blue color is

formed.

Presence of protein

with free –NH2

group

4 Millon’s test:

To a little amount of the substance

is treated with Millon’s reagent

(Eg. Egg Albumin)

White precipitate is

obtained, which turns to

brick red colour on

heating

Presence of protein

with –OH group

5 Molisch’s Test:

To a little amount of substance is

treated with Molisch’s reagent and

con. H2SO4 drop wise to the sides

Violet ring at the

junction of two layers is

formed

Presence of protein

with carbohydrates

as prosthetic


12

of the test tubes

6 Lead Sulfide test:

Boil the protein solution with

40% NaOH and lead acetate

solution

Black precipitate is

formed

Presence of protein

with thiol/disulphide

linkages


13

E. ANALYSIS OF CARBOHYDRATES

S.No. Test Observation Inference Reaction

1 Molisch’s Test

2-3 drops of beta-

naphthol solution

are added to 2ml of

the test solution.

Very gently add

1ml of Conc.

H2SO4 along the

side of the test

tube.

A deep violet

coloration is

produced at the

junction of two

layers.

Presence of

carbohydrates.

This is due to the

formation of an

unstable

condensation

product of beta-

naphthol with

furfural (produced

by the dehydration

of the

carbohydrate).

2

Iodine test

4-5 drops of iodine

solution are added

to 1ml of the test

solution and

contents are mixed

gently.

Blue colour is

observed.

Presence of

polysaccharide.

Iodine forms

coloured adsorption

complexes with

polysaccharides.


14

3 Fehling's test

About 2 ml of sugar

solution is added to

about 2 ml of

Fehling’s solution

taken in a test-tube.

It is then boiled for

10 min.

A red precipitate

is formed

Presence of reducing

sugar

This is due to the

formation of

cuprous oxide by

the reducing action

of the sugar.

4 Benedict’s test

To 5 ml of

Benedict's solution,

add 1ml of the test

solution and shake

each tube. Place

the tube in a boiling

water bath and heat

for 3 minutes.

Remove the tubes

from the heat and

allow them to cool.

Formation of a

green, red, or

yellow precipitate


sugars

If the saccharide is

a reducing sugar it

will reduce Copper

Cu(II) ions to Cu(I)

oxide, a red

precipitate

5 Barfoed’s test

To 2 ml of the

solution to be tested

added 2 ml of

freshly prepared

Barfoed's reagent.

Place test tubes into

a boiling water bath

and heat for 3

minutes. Allow to

cool.

A deep blue color

is formed with a

red ppt. settling

down at the

bottom or sides of

the test tube.


sugars. Appearance

of a red ppt as a thin

film at the bottom of

the test tube within 3-

5 min. is indicative of

reducing mono-

saccharide. If the ppt

formation takes more

time, then it is a

reducing

disaccharide.

If the saccharide is

a reducing sugar it

will reduce Cu(II)

ions to Cu(I) oxide


15

6 Seliwanoff test

To 3ml of

Seliwanoff’s

reagent, add 1ml of

the test solution.

Boil in water bath

for 2 minutes.

A cherry red

colored precipitate

within 5 minutes

is obtained.

A faint red colour

produced

Presence of ketoses

[Sucrose gives a

positive ketohexose

test]

Presence of aldoses

When reacted with

Seliwanoff reagent,

ketoses react within

2 minutes forming a

cherry red

condensation

product

Aldopentoses react

slowly, forming the

coloured

condensation

product.

7 Bial's test

Add 3ml of Bial’s

reagent to 0.2ml of

the test solution.

Heat the solution in

a boiling water bath

for 2 minutes.

A blue-green

product

A muddy brown to

gray product

Presence of pentoses.

Presence of hexoses.

The furfural formed

produces

condensation

products with

specific color.


16

8 Osazone Test

2ml of the test

solution, add 3ml of

phenyl hydrazine

hydrochloride

solution and mix.

Keep in a boiling

water bath for

30mts. Cool the

solution and

observe the crystals

under microscope.

Formation of

beautiful yellow

crystals of osazone

needle shaped

crystals

Hedgehog crystals

Sunflower shaped

crystals

Glucose/fructose

Presence of lactose

Presence of maltose

Reducing sugars

forms ozazone on

treating with

phenylhydrazine


17

F. IDENTIFICATION OF SIMPLE ORGANIC COMPOUNDS

1. QUALITATIVE ANALYSIS OF ORGANIC COMPOUNDS

S.NO EXPERIMENT OBSERVATION INFERENCE

1 COLOUR

Colour of the substance

is observed

Yellow

Dark brown

Colorless

Presence of aromatic nitro

compound, diketones.

Presence of aromatic amine,

Phenol.

Presence of aromatic acid,

ketone, ester, Carbohydrate.

2 ODOUR

Odour of the substance

is noted

Pleasant/Fruity

Phenolic

Aniline like

Presence of ester

Presence of Phenol.

Presence of aromatic amine

3 SOLUBILITY TEST:

To a little sample of

substance add a distilled

water and shaken well

Soluble in cold water

Soluble in hot water

Presence of Carbohydrate,

polyhydric Phenol, certain

acids.

May be Carboxylic acid or

Phenol

4 LITMUS TEST

To about 0.1g of the

substance 1ml of

distilled water and

shaken well. Tested

with the litmus paper.

Blue turns red

Red tuns blue

May be Carboxylic acid or

Phenol

May be aniline

5.DETECTION OF ELEMENT: PREPARATION OF SODIUM FUSION EXTRACT:

A small dry pellet of sodium is taken in a test tube and add 0.1g of the substance is

added, heated gently at first and then strongly till the bottom of the tube becomes red hot. The


18

red hot end of the tube is plunged into 10ml of distilled water in a china dish, ground well,

boiled and filtered. The filtrate is known as sodium fusion extract. The extract is used for the

following tests.

5a To about 1ml of this

extract, add a few

crystals of ferrous

sulphate, boiled, cooled,

acidified with 2ml of

H2SO4

Blue or green precipitate

Presence of Nitrogen

5b To about 1ml of this

extract, 1ml;of dilute

nitric acid is added,

boiled, cooled, and then

added Silver Nitrate

solution.

White precipitate soluble

in aq. NH3

Pale yellow precipitate

partially soluble in aq.

NH3

Deep yellow precipitate

insoluble in aq. NH3

Presence of Chlorine

Presence of Bromine

Presence of Iodine

5c To about 1ml of the

extract, few drops of

Sodium Nitroprusside

solution are added.

Violet color

Presence of Sulphur

6

a

TEST FOR

ALIPHATIC OR

AROMATIC:

FLAME TEST:

About 0.1g of the

substance is ignited in a

nickel spatula

Burns with a luminous

smoky flame

Burns with a non

luminous flame

Presence of aromatic

compound

Presence of aliphatic

compound


19

b NITRATION TEST:

About 0.2g of the

substance is mixed with

conc.HNO3 and 1ml of

H2SO4. It is heated,

boiled, cooled and pour

into 20ml of cold water.

Yellow precipitate or

color is obtained

No Yellow coloration


compound

Presence of aliphatic

compound

7

a

b

TEST FOR

SATURATION AND

UNSATURATION:

Bromine Test

Dissolve a little of the

given organic

compound in about 2 ml

of distilled water in a

test tube and add few

drops of bromine water

to it and shake well.

Baeyer's Test

(Alkaline

KMnO4 Test)

Dissolve a little of the

given organic

compound in about 2 ml

of distilled water in a

test tube and add few

drops of alkaline

solution of KMnO4 to it

and shake well.

Disappearance of

orange-red color of

Bromine.

No disappearance of

orange-red color.

Disappearance of pink

color of KMnO4.

No disappearance of

pink color of KMnO4.

Presence of unsaturated

compound

Presence of saturated

compound

Presence of unsaturated

compound

Presence of saturated

compound


20

8

ACTION OF

SODIUM

CARBONATE:


substance, 2ml of

saturated NaHCO3

solution is added.

Brisk effervescence with

evolution of CO2 which

turns lime water milky.

Presence of Carboxylic acid

9 ACTION OF DILUTE

HCl:


substance, 2ml of

dil. HCl is added,

shaken well.

Dissolution with

precipitation on adding

10% NaOH drop wise

Presence of basic functional

groups.

10 ACTION OF

SODIUM

HYDROXIDE:


substance, 2ml of 10%

NaOH is added, shaken

well.

Dissolution with

precipitation on addition

of conc. HCl

Dissolution with strong

yellow color which

disappears by addition of

conc. HCl

Evolution of NH3 gas

Solution turns yellow or

brown on boiling

Oily globules with

aniline smell on boiling

Presence of aromatic acid or

phenol


nitrocompound or aldehyde

Presence of amide or

ammonium gas.

Presence of sugar or aliphatic

aldehyde

Presence of anilide


21

Oily layer that

disappears on boiling,

white precipitate on

acidification with

conc. HCl and cooling.

No characteristic change

in cold or boiling

condition

Presence of ester or amide of

aromatic acid.

Presence of nitro compound,

ketone or amine.

11 ACTION OF CONC

H2SO4


substance, 1ml of conc.

H2SO4 is added and

heated gently.

Solution becomes black

with the smell of burnt

sugar

Violet reaction

Presence of polyhydride

alcohol or carbohydrate.

Presence of aliphatic or

aromatic alcohol.

12 ACTION OF SODA

LIME:


substance, 1ml of soda

lime is added and

heated strongly.

Liberation of ammonia

gas.

Kerosene smell

Phenolic smell

Presence of amide or

ammonium gas.

Presence of carboxylic acid

Presence of phenolice acid or

ester.

13 ACTION OF

NEUTRAL

FERRICCHOLRIDE:

To the amount of 0.1g

substance, neutral FeCl3

solution is added

Violet, blue or green

color

Blue precipitate

Presence of phenol

Presence of naphthylamine or

naphthol


22

Brown precipitate

Yellow color

Presence of carboxylic acid

Presence of hydroxyl acid

14 ACTION OF

TOLLEN’S

REAGENT


substance, 2ml of

Tollen’s reagent is

added and heated in a

boiling water bath for

10 minutes.

Black precipitate or

silver mirror

Presence of reducing sugar

Presence of aldehydes

TEST FOR FUNCTIONAL GROUPS

15 TEST FOR ACIDS

a. Esterfication:


substance, added 1ml

rectified spirit and a5

drops conc. Sulphric acid

shaken well & warmed

gently. the mixture is

poured into 10ml of dil.

Na2CO3 solution

Pleasant odour

Presence of organic acid

b. Phenolphthalein test

About0.1g substance is

dissolved in 1ml water

and added a drop of

phenolphthalein and pour

into NaOH solution

Pink colour is formed

Presence of organic acid


23

c Flourescein

About 0.1g of the

substance is mixed with

0.5g resorcinol and 4

drops of conc. H2SO4 in

a glass tube. Heated for

3-5 minutes and poured

into dil. NaOH solution.

Intense greenish yellow

fluorescence is obtained

Presence of dicarboxylic acid

16.

a

b

TEST FOR

ALCOHOLS

Acetylation test:

A little of the substance

is heated with glacial

acetic acid and a few

drops of

con.H2SO4.Then cooled

and poured into excess of

water containing little

sodium carbonate

solution.

Action with sodium:

To a little of the

substance a bit of dry

sodium is added.

Pleasant fruity odour is

formed.

Effervescences is noted

Presence of alcohol is

confirmed.

Presence of alcohol is

confirmed.

16 TEST FOR PHENOLS

a Ferric chloride Test:

Take about 1 ml of

neutral ferric chloride

solution in a clean test

Violet colour is seen. Presence of phenolic group.


24

tube and add 2-3 drops

of the given liquid (or

crystal is solid).

b Phthalic anhydride

test:


substance, about 0.5g of

Phthalic anhydride and 3

drops of conc. H2SO4 are

added. Heated gently for

2-3 minutes and poured

into 20ml dil. NaOH

solution.

Pink color solution is

formed

Greenish yellow color

solution is obtained.

Presence of monohydric

phenol

Presence of dihydric phenol

c Dye Test:

About 1ml of aniline is

dissolved in 4ml of

dil. HCl, the solution

cooled under tap or ice

water and added NaNO2

solution drop wise. To

this solution 0.5g of the

substance dissolved in

5mlof dil. NaOH

solution is added slowly.

Orange dye

Scarlet or red dye

Presence of Phenol

Presence of naphthol or

resorcinol

d Libermann’s Test:

About 0.1g substance is

mixed with 0.5g NaNO2

in a dry test tube, heated

for 2 minutes and cooled.

5 drops of conc. H2SO4 is

added. Bluish green

Red solution becomes

deep blue with excess

NaOH

Presence of phenols(not

substituted phenols)


25

solution is poured into

30ml water in a beaker

and NaOH added in

excess.

17 TEST FOR ESTER

a

Hydrolysis:

To about 0.2g of

substance add 2ml of

10% NaOH solution and

boiled for 3minutes.It is

then cooled and add 1ml

of conc. HCl

Disappearance of

pleasant odour


obtained

Presence of ester

Presence of aromatic ester

b Test with

phenolphthalein:

To about 0.2 g of the

substance, add 2 drops of

phenolphthalein and 3

drops of NaOH solution

is added and heated.

Disappearance of pink

colour

Presence of ester

C Hydroxamic acid test:

To a few drops of the

substance add 0.2g of

hydroxylamine

hydrochloride and about

5ml of 10%NaOH and

the mixture is gently

boiled for 2minutes.

Cooled and acidified

with dil. HCl and then

added few drops of

A violet or deep red

/brown colour

developed immediately

Presence of ester is confirmed


26

FeCl3 solution

18 TEST FOR

ALDEHYDES AND

KETONES

a Borsche’s Test: To

about 0.1g of the

substance dissolved with

water and Borsche’s

reagent are added and

boiled with conc.HCl.

Yellow or orange

precipitate is obtained

Presence of aldehyde or

ketone

b Phenyl hydrazine Test:

To a few drops of

substance add water or

ethanol and heated with

1ml of Phenyl hydrazine

on a boiling water bath

for 10 minutes.

Yellow precipitate

Yellow crystals

Presence of aldehyde or ketone

Presence of carbohydrates

c Semicarbazide Test:

To about 0.2g substances

add a mixture of 0.2

semicarbazide

hydrochloride, 0.5g

sodium acetate and 2ml

water. 7m lof alcohol is

added to get clear

solution, heated for 2

minutes and cooled.

Colourless crystal

Presence of aldehydes or

ketones

d Schiff’s reagent test:


substance add 3-4 drops

Immediate pink or red

colour

Presence of aldehyde


27

of schiff’s reagent,

shaken well.

Slow pink colouration Presence of aliphatic ketone

e Fehling’s Test:



Fehling”s A and B

solution and boiled

Red precipitate

Presence of aldehyde or ketone

f Tollen’s Reagent:

To a few drops of


Tollen’s reagent and

heated on water bath for

5-10 minutes.

Black precipitate or

bright silver mirror

Presence of aldehyde is

confirmed

g Legal Test:

To a few substances add

some ml of water; add 5

drops of sodium

nitroprusside solution,

5 drops of NaOH and

5 drops of glacial acetic

acid solution.

Orange colour turns

purple

Presence of Ketone

h. m-Dinitrobenzene Test:

Take a small quantity of

the given compound in a

clean test tube and add

about 0.1g of finely

powdered m-

dinitrobenzene. Now add

about 1 ml of dilute

sodium hydroxide

Violet colour is formed

which slowly fades

away.

Presence of ketonic group is

confirmed.


28

solution and shake it

well.

19 TEST FOR CARBOHYDRATES

a Mollisch’s Test:

To about 0.1g of substance

in 1ml of water,add 1ml of

alcoholic α-naphthol

solution, shaken well and

conc. H2SO4 added

dropwise through the sides.

Deep violet ring at the

junction between the two

layers

Presence of

carbohydrates

b Barford’s test

To a little of the substance

in water, barford’s reagent is

added and heated in a water

bath.

A red brown precipitate is

obtained.

Presence of

monossacharides like

glucose, fructose is

confirmed.

c Rapid furfural test:

About 1ml of a dilute

solution of given organic

substance in water is mixed

with 1ml of a 1% alcoholic

solution of alpha napthol

and then about 6ml of conc.

HCl. The mixture is then

boiled for two minutes.

Violet coloration is

produced when the solution

just started boiling.

Presence of

carbohydrate is

confirmed.

20 TEST FOR AMINE


29

a Action with Nitrous acid

A little of the substance is

dissolved in 3ml of dil. HCl.

Then a strong solution of

NaNO2 is added drop by

drop, cooling the mixture

well.

A clear solution

Yellow oily liquid

Reddish brown solid

May be aromatic

primary amine

Presence of secondary

amine

Presence of tertiary

amine

b Dye Test


dissolved in 2ml dil. HCl,

cooled under tap water or

ice water and add a mixture

of 1ml of NaNO2 solution

and I ml of β-naphthol

dissolved in NaOH.

Scarlet red dye

Presence of primary

amine confirmed

c Acetylation

To about 0.1g substance add

1ml of acetic acid, 0.5ml of

acetic anhydride, heated

gently for 3-5 minutes and

poured into 20ml of water in

a beaker.

White crystals

Presence of primary

amine confirmed

d

Libermann’s Test


dissolved in 3ml ethanol. To

this 1ml of conc. HCl added,

cooled under tap or ice

water and 1ml of NaNO2

solution added. Shaken well,

Red solution turns blue

Presence of secondary

amine confirmed


30

ether layer separated and

evaporated carefully. 5

drops of phenol added to the

residue, warmed, cooled and

added 5 drops of conc.

H2SO4 and poured into

20ml of dil. NaOH solution

e With Sodium hydroxide

To the reddish brown solid

sodium hydroxide is added

Green color precipitate

Presence of tertiary

amine is confirmed

21 TEST FOR AMIDE

a Urea nitrate Test


add 1ml of water and1ml of

conc.HNO3, shaken well.


obtained

Presence of diamide

b Urea Oxalate Test

About 0.1g of substance is

shaken with 3ml of saturated

oxalic acid solution.

White precipitate is formed

Presence of diamide

c Biuret Test

About 0.2g of substance is

strongly heated in dry test

tube till NH3 smell ceases.

Cooled and added 1mlof

water and 4 drops of CuSO4

and NaOH solution.

Violet color

Presence of diamide

22 TEST FOR NITRO GROUP


31

MULLIKEN AND BARKER’S TEST:

About 0.1g substance is dissolved in 2ml of ethanol and add 0.5g of NH4Cl and

Zn dust, heated for 2 minutes and allowed to stand for 3 minutes and filtered. Filtrate

is divided into two parts.

a To a few drops of substance

add 1ml of Tollen’s reagent

and heated on water bath for

5-10 minutes.

Black precipitate or bright

silver mirror

Presence of

nitrocompound

b To about 0.1g of the


Fehling’s A and B solution

and boiled

Red precipitate

Presence of

nitrocompound

c Reduction:


add 5ml of conc. HCl and a

piece of Sn. Heated for 3-5

minutes and KOH solution

added till it becomes

alkaline. Separated liquid is

tested for amines

Positive observations for

amines

Presence of nitro

compound

23 TEST FOR ANILIDE

a About 0.1g substance is

dissolved in 3ml glacial

acetic acid and added 1ml of

Br2 in acetic acid. Shaken

well and poured into 10ml

of water.

Pale yellow precipitate

Presence of anilide


32

b Dye Test:


dissolved in 2ml dil. HCl,

under tap water or ice water

and add a mixture of 1ml of

NaNO2 solution and I ml of

β-naphthol dissolved in

NaOH.

Scarlet red dye

Presence of anilide

24 TEST FOR HYDROCARBONS:

a Nitration test:

To a little of the substance is

treated with a mixture of

1ml of con. H2SO4 and 1ml

of Con.HNO3 and heated on

a water bath for 10 minutes.

The contents are cooled and

poured into water.

Yellow precipitate or oily

drops formed

Presence of

hydrocarbon is

confirmed

b Picrate Test:

To 1ml of saturated solution

of substance in alcohol, 1ml

of similar solution of picric

acid is added and allows to

evaporate.

Golden yellow crystals

Presence of

hydrocarbon is

confirmed

Result:

Aliphatic/Aromatic

Saturated / Unsaturated

Presence of functional group

Respective derivatives


33

2. PREPARATION OF DERIVATIVES

1. ACIDS

a. Anilide Derivative(for aromatic acids):

1g substance is mixed with 5ml aniline in boiling tube. A porcelain bit is added, fitted

with air condenser and heated for 30 minutes in a sand bath. The mixture is allowed to stand

for 10-15 minutes. The separated white precipitate of anilide is filtered, washed with cold

water and recrystallized from alcohol.

b. Nitro Derivative(for unsaturated acids):

1g of the substance is mixed with 2ml fuming nitric acid slowly with constant stirring

in a dry test tube aside for 10-15 minutes. Then poured into 50 ml distilled water in a beaker.

The separated yellow crystals are filtered at pump, washed with water and recrystallized from

alcohol.

c. Bromo Derivative (for aromatic acids):

1g of substance is mixed with 5mlof bromine in glacial acetic acid with constant

stirring till yellow color develops. Shaken well for 10-15 minutes and poured into 50ml water

with constant stirring. The yellow crystals are filtered, washed with water and recrystallized

from alcohol.

2. PHENOLS

a. Bromo Derivative:


stirring till yellow color develops. Shaken well for 10-15 minutes and poured into 50ml water

with constant stirring. The yellow crystals are filtered, washed with water and recrystallized

from alcohol.

b. Nitro Derivative:

1g of substance is mixed with 2ml of conc. H2SO4, warmed gently for

2minutes.Cooled and added 2ml conc. HNO3 drop wise. Heated for 10 minutes and poured

into 20ml water in a beaker. Yellow solid is recrystallized from boiling water.


34

c. Benzoyl Derivative:

To 0.5 g substance add 2ml water, 0.5 ml benzoyl chloride and 5ml NaOH solution.

Shaken well for 5 minutes and poured into 20ml water in a beaker. White precipitate is

obtained.

3. ESTERS

a. Acid Derivative:

0.5g of substance is mixed with 10ml of 10%NaOH solution, heated for 2-4minutes

and added conc. HCl. White precipitate is obtained.

b. Amide Derivative:

0.5 g of substance is mixed with 5ml of liquor NH3 shaken well and left for 10

minutes. White precipitate is formed.

4. ALDEHYDES AND KETONES

a. Semicarbazone Derivative:

Mix 0.5g of the substance with 0.5g semicarbazide hydrochloride and 0.5g sodium

acetate solution. Heated gently for 10 minutes and poured into water. White crystal is

obtained.

b. Phenyl hydrazone Derivative:

Mix 0.5g of the substance with 1ml of phenyl hydrazine and 1ml of glacial acetic acid

solution. Heated gently for 10 minutes and poured into water. Yellow crystal is obtained.

c. 2, 4-dinitrophenyl hydrozone Derivative:

To 0.5g of substance add 1ml of Borche’s reagent and conc. HCl solution. Heated gently for

10 minutes and poured into water. Yellow crystal is obtained.

5. ACID DERIVATIVE (for aromatic aldehydes):

1g of substance is mixed with 1ml of 5% Na2CO3 solution, KMnO4 solution is added

drop wise till the color remains. Heated for 10 minutes and added dil. H2SO4, a strong

solution of sodium sulphite till the solution becomes colorless. On Cooling, white crystals

separate out.


35

6. CARBOHYDRATES

Phenylhydrazone Derivative:

Mix 0.5g of the substance with 1ml of phenyl hydrazine and 1ml of glacial acetic acid

solution. Heated gently for 10 minutes and poured into water. Yellow crystal is obtained.

7. AMINES

a. Benzoyl Derivative:

To 0.5 g substance add 2ml water, 0.5 ml benzoyl chloride and 5ml NaOH solution.

Shaken well for 5 minutes and poured into 20ml water in a beaker. White precipitate is

obtained.

b. Acetyl Derivative:

0.5g substance is mixed with 1ml acetic anhydride and 1ml glacial acetic acid, heated

for 10 minutes and poured into 20ml water. White crystals are obtained.

8. AMIDES

Acid Derivative:

1g of substance is mixed with 1ml of 5% Na2CO3 solution, KMnO4 solution is added

drop wise till the color remains. Heated for 10 minutes and added dil. H2SO4, a strong

solution of sodium sulphite till the solution becomes colorless. On Cooling, white crystals

separate out.

9. NITRO GROUP

The nitro compounds are reduced to the amines by treatment with Sn/HCl and the

amines are converted into benzoyl or acetyl derivative as mentioned above.

10. ANILIDE

Bromo Derivative:


stirring till yellow color develops. Shaken well for 10-15 minutes and poured into water with

constant stirring. The yellow crystals are filtered, washed with water and recrystallized from

alcohol.


36

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