Semi Micro Qualitative Organic chemistry lab manual

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DOS & R in Organic Chemistry, Tumkur University, Tumakuru
TUMKUR UNIVERSITY
TUMAKURU
DEPARTMENT OF STUDIES AND
RESEARCH IN ORGANIC CHEMISTRY
ORGANIC CHEMISTRY PRACTICAL
MANUAL
Prepared By
Dr. S. Sreenivasa Ph.D., D.Sc.
Associate Professor
Dr. G. Krishnaswamy Ph.D.
Faculty
2018-19

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SEPERATION OF BINARY ORGANIC MIXTURE FLOW CHART

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Systematic analysis and identification of Organic Compounds
In Qualitative analysis the given mixture is analyzed for functional groups that it contains.
Depending upon the quantity of sample used it is classified as
Macro Analysis ------------- 0.1 – 1g
Semi-micro Analysis ------ 10 – 100 mg
Micro Analysis ------------- 1 – 10 mg
The analysis of the given organic compound is carried out in the order.
I. Preliminary tests.
II. Determination of physical constant (boiling point or melting point)
III. Detection of elements (nitrogen, sulphur and halogens).
IV. Solubility test.
V. Characteristic reactions of the functional group.
VI. Preparation of suitable solid derivative.
VII. Report
I. PRELIMINARY TESTS:
Test Observation Inference
a) Physical State Solid/Liquid
b) Color
colorless
Hydrocarbons, Carbohydrates,
Alcohols, Phenols, Aldehydes,
Ketones, acids, esters
Yellow Nitro compounds
Greenish yellow p-Nitroso compounds
Reddish orange
Nitroamines, azocompounds,
Napthaquinones
c) Odor Pleasant -fruity Esters
Bitter almond odor
Benzaldehyde, nitrobenzene,
benzonitrile
Odor of carbolic soap Phenols, Cresols
Pungent or irritating
Lower acids, aldehydes, acid
halides
Fishy odor
Aliphatic amines, side chain
aromatic amines
Sweet odor Chloroform, alcohols
Vinegar like Acetic acid
Cinnamon like Cinnamaldehyde
d) Ignition test:
Heat the organic compound
on a spatula over a low
flame, raising the
temperature
gradually
Burns with a sooty flame Aromatic compounds
Burns without sooty flame Aliphatic compounds
Ammoniacal odour Urea, Thiourea
Charring with the smell of
burnt sugar
Carbohydrates , tartarates,
Citrates

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e) (Test for unsaturation)
A)Baeyer’s test:
A pinch or a drop of the
organic compound + about
one cm3
of 5% Sodium
carbonate solution +one
drop of 1% KMnO4
solution
Pink color discharged without
brown precipitate
Unsaturated compound
Pink color discharged with
brown precipitate
Or
No decolorisation
Saturated compound
B) Bromine water test:
A pinch or a drop of the
organic compound + Br2
water
Decolorization of Br2 water Unsaturated compound
C) Bromine in CCl4 test:
Dissolve a pinch or a drop
of the organic compound in
about 2 ml of CCl4, add 2%
solution of Br2 in CCl4
Decolorization without
evolution of HBr Unsaturated compound
Decolorization with evolution
of HBr Saturated compound

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f) Beilstein’s test:
A copper wire is ignited in non
luminous flame till it does not
impart green color. Then it is
plunged into the given organic
compound and again ignited.
Green edged flame
The given compound may be
special amide
Or
The given compound contains
halogen.
g) Litmus test:
Substance (if liquid) or the solution of the substance in neutral aq. alcohol + moist litmus paper
i)Blue litmus turns red Acidic compounds(carboxylic acids, phenols)
ii)Red litmus turns blue Basic compounds(amines)
iii)No change of color Neutral compounds
II. DETERMINATION OF PHYSICAL CONSTANT: (BOILING POINT OR
MELTING POINT)
If the given compound is a solid determine the melting point is determined, if it is a liquid
determine its boiling point is determined.
Note: Since the boiling point decreases by one degree for every 1000 feet altitude above
the sea level;
Corrected boiling point = observed boiling point +/- 3 % correction
Physical constant
Melting point: o
C
Boiling point: o
C
Observed boiling point
3% correction
Corrected boiling point o
C
o
C
III. DETECTION OF ELEMENTS BY SODIUM FUSION TEST OR
LASSAIGNE’S TEST ( NITROGEN , SULPHUR AND HALOGENS):
In order to detect the elements in organic compounds, it is necessary to convert them into
ionizable inorganic substances so that the ionic tests of inorganic qualitative analysis may be
applied.
This conversion may be accomplished by several methods, but the best procedure is to fuse
the organic compound with metallic sodium (Lassaigne’s test).
Lassaigne’s test consists of
(a) Preparation of Sodium fusion extract
(b) Test for elements(Nitrogen, Sulphur or halogen)
Cu O2 2 CuO 4R-X 2CuX2
2CuX2 Blue-Gree Light

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(a) Preparation of Sodium fusion extract:
Take a small piece of clean dry sodium (approx.50-75 mg) in a clean dry ignition tube. Heat
the tube slowly just to melt the Sodium into a silvery globule. Remove it from the flame and
add the compound (20-25 mg or a drop).First heat on a low flame and then on a stronger
flame until it becomes red hot. Keep it in the red hot condition for 1-2 minutes (until the
compound completely reacted) and then plunge into 10-15 ml of distilled water kept in a
porcelain basin. Boil the contents of the porcelain basin for 2-3 minutes and filter .This
filtrate is called Sodium fusion extract or stock solution .The filtrate, the Lassaigne’s extract,
is used for testing the extra elements.
Note: The filtrate should be colorless. Repeat the experiment if the filtrate is not colorless.
Na +C + N → NaCN
2Na+S →Na2S
Na + X →NaX (X= Cl , Br , I)
Na+ C+ N+ S → NaSCN
Precautions:
1. Do not touch Sodium with your fingers; handle it with forceps.
2. There may be a slight explosion with compounds like nitroalkanes , azides, diazonium
salts, chloroform and carbon tetrachloride.(safety goggles should be worn to avoid getting
hurt by accidents).

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(b) Test for elements(Nitrogen, Sulphur or halogens)
Test for Nitrogen
Experiment Observation Inference
1cm3
of stock solution+ few
crystals of Ferrous sulphate
(50-70mg), boiled; cooled +
dil.H2SO4 or dil. HCl
A blue precipitate
or
A Green solution
Nitrogen is present
Test for Sulphur:
1cm3
of stock solution + few drops
of 1% sodium nitroprusside
solution and shake well.
Purple or pink colour Sulphur is present
S2- + [Fe(CN)5NO]2- → [Fe(CN)5NOS]4-
1cm3
of stock solution+ acetic acid
+ lead acetate
Black precipitate Sulphur is present
Pb(CH3COO)2 + S2-→ PbS ↓ + 2CH3COO-
Test for halogens:
a)1cm3
of stock solution + a few
drops of Conc.HNO3
Boiled, cooled + Silver nitrate
solution drop by drop.(If N and S are
absent ,boiling is not required)
White precipitate easily
soluble in NH4OH
Chlorine is present
Pale yellow precipitate
sparingly soluble in NH4OH
Bromine is present
Yellow precipitate soluble
in NH4OH
Iodine is present
NaCl + AgNO3 AgCl↓ + NaNO3
white precipitate
AgCl↓ + NH4OH → [Ag(NH3)2]Cl + 2H2O
Soluble complex
FeSO4 2 NaOH Fe(OH)2 Na2SO4
Fe(OH)2 2 NaCN Fe(CN)2 2 NaOH
Fe(CN)2 2 NaCN Na4[Fe(CN)6]
3 Na4[Fe(CN)6] 4 FeCl3 Fe4[Fe(CN)6]3 12 NaCl
Ferric ferrocyanide
(Prussian blue color)
Na4[Fe(CN)6] 2 Fe2(SO4)3 Fe4[Fe(CN)6]3 Na2SO4
Ferric ferrocyanide
(Prussian blue color)
[OR]

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NaBr + AgNO3 AgBr↓ + NaNO3
Pale yellow precipitate
NaI + AgNO 3 AgI↓ + NaNO3
Yellow precipitate
i) Globule test:(Distinction among halogens : To be performed if the above test is positive)
b) 1cm3
of stock solution add about 2
ml of dil.HCl till acidic + few
drops of CCl4+dropwise addition of
freshly prepared Chlorine water &
shaken well.
Colorless globule Chlorine is present
Orange red globule Bromine is present
Violet globule Iodine is present
Preparation of Chlorine water:
A drop of KMnO4+Conc.HCl is added dropwise till colorless. The clear solution contains
dissolved Chlorine.
Globule test:
Acidify a small portion of Lassaigne’s extrct with dil HCl and add a few drops of CCl4.Now
add freshly prepred Chlorine water and shake vigorously.
(a) Cl2 + NaBr → Br2 + 2NaCl
( From sodium fusion extract)
Appearance of orange color in the CCl4 layer indicates the presence of Bromine
(b) Cl2 + NaI → Br2 + 2NaI
( From sodium fusion extract)Appearance of violet color in the CCl4 layer indicates the
presence of Iodine.

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IV. SOLUBILITY TEST:
The purpose of this test is to find out the correct group to which the organic compound
belongs. For this purpose different solvents are tried and the solubility of the compound is
determined. This gives the group and probable functional group in that solubility group. Then
characteristic reactions for the various classes of compounds of that group are carried out to
find the extra functional group.
A drop of the organic liquid or a pinch of the organic solid is shaken well with the following
order.
1. Water
2. Ether (if soluble in water)
3. 5% HCl
4. 5% NaOH
5. 5% NaHCO3
6. Conc.H2SO4
The following instructions must be followed while carrying the solubility test:
1. If the compound is soluble in water, solubility in ether should not be carried out .
2. While doing the solubility test with Conc. H2SO4 or ether , a dry test tube must be
used.
3. The above order of solvents should not be changed.
4. If the organic compound is soluble in earlier groups , it is not necessary to proceed
further
5. If the compound contains Nitrogen and is insoluble in water and 5% HCl it belongs to
VII group. Then solubility in 5% NaOH and Conc.H2SO4 need not be carried out.
6. Solubility of organic solid or liquid is indicated by the formation of homogeneous
solution.
7. Formation of a precipitate or color or evolution of heat is also an indication of
solubility in con. H2SO4.
8. Write the solubility chart and use (+) or (-) sign (i.e. leave it blank) for the groups for
which the solubility test is not carried out.
9. Write the inference indicating the solubility (group) and classes of compounds.

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SOLUBILITY TABLE
Soluble In water Insoluble in Water
Soluble in ether
Insoluble in
ether
(Nitrogen
present or
absent)
Soluble in 5%
HCl
(Nitrogen
present)
Soluble in 5% NaOH Nitrogen absent Nitrogen present
Soluble in 5%
NaHCO3
Insoluble in
5%
NaHCO3
Soluble in cold
concentrated
H2SO4
Insoluble in
cold
concentrated
H2SO4
Indifferent group
I Group II Group III Group IV A Group IV B Group V Group VI Group VII Group
R-NH2
R-OH
R-COOH
R-CHO
R-CO-R’
(low MW)
H2N NH2
O
CHO
OHH
HHO
OHH
OHH
CH2OH
NH2
R R
OH
O OH
R
R
H
O
R
R'
O
R
OR
O
X
X
NHR
O
H
N
O
NO2

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V. FUNCTIONAL GROUP ANALYSIS
CHARACTERISTICS REACTIONS FOR I GROUP COMPOUNDS
REACTIONS OF ALCOHOLS
EXPERIMENT OBSERVATION INFERENCE
Neutral Ferric chloride Test
A pinch or a drop of organic
compound dissolved in water
+ a few drops of neutral
ferric chloride solution.
No Violet or pink
Or
Dirty green solution
It is a Alcohol
Ceric ammonium nitrate
+ a few drops of ceric
ammonium nitrate solution
Red color observed It is a Alcohol
Bromine water Test
compound + water + bromine
water drop wisely with
shaking
No white precipitate It is a Alcohol
Chromic acid Test
compound + few crystals of
K2Cr2O7 + dil. HCl
Green precipitate Primary / Secondary alcohol
No green precipitate Tertiary alcohol
Lucas test
compound + A solution of
zinc chloride in concentrated
hydrochloric acid.
Cloudy dispersion or separate
layer immediately
Tertiary alcohol
Cloudy dispersion upon
standing
Secondary alcohol
Heating required to reaction to
occur
Primary alcohol
2 R OH (NH4)2Ce(NO3)6 (ROH)2Ce(NO3)6 2 NH4NO3
Alkoxy cerium (IV)compound
(Pink or Red color)

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CHARACTERISTIC REACTIONS FOR II GROUP COMPOUNDS:
REACTIONS OF AMIDES
Alkali test
compound + 10 % NaOH, boiled
and exposed to a wet red litmus
paper to the vapours.
A glass rod dipped in Conc. HCl
is exposed to the vapours.
Pungent smelling gas
which turns red litmus
blue.
Dense white fumes are
formed
It is an Amide
Biuret test
compound is heated in a dry test
tube till all ammonia is expelled
in the form of white fumes. The
solid melts and then solidifies on
cooling. To the white residue a
few drops of NaOH solution + A
few drops of CuSO4 Solution
along the sides of the test tube.
Pink or purple solution. It is a special Amide ( Urea )

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REACTIONS OF SUGARS: (Carbohydrates)
compound + con. H2SO4 and
heated.
Charring takes place and
a black product is formed
It is a carbohydrates
Molisch’s test
Solution of the compound in
water + alcoholic α- napthol
soloution + Conc. H2SO4 along
the sides of the test tube.
Violet ring is formed It is a carbohydrate
Sliver mirror test
water + Tollen’s reagent. The
test tube is heated on a water
bath.
Silver mirror
Or
Black precipitate
Reducing Sugar
No silver mirror
Or
No black precipitate
Non reducing sugar
Preparation of Tollen’s regent: A few drops of silver nitrate + a drop of sodium hydroxide
to get a brown ppt + ammonium hydroxide drop wisely till the brown ppt. Just disappears.
The clear solution is called Tollen’s reagent
Benedict’s test
water + Benedict’s solution,
boiled
Green brown or red
colour
Reducing sugar
No change Non reducing sugar
CHO
OHH
HHO
OHH
OHH
CH2OH
O
HO
CHO
OH
OHO
O
OH
H2SO4
-3H2O
H2SO4
-H2O
Purple- colored dye
[O]
Hexose
5-hydroxymethyl
furfural 1-naphthol
CHO
OHH
HHO
OHH
OHH
CH2OH
[Ag(NH3)2]OH
Hexose
(Tollens reagent)
COO-
NH4
+
OHH
HHO
OHH
OHH
CH2OH
Gluconic acid
Ag
Silver
mirror

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.
CHO
OHH
HHO
OHH
OHH
CH2OH
Cu(Citrate) complex
Hexose
(Benedicts reagent)
COOH
OHH
HHO
OHH
OHH
CH2OH
Gluconic acid
Cu2O
Brick-Red
Precipitate
HO
O
OH
OOH
OHO
Cu2+

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CHARACTERISTIC REACTIONS OF III GROUP COMPOUNDS
REACTIONS OF AMINES
compound in a dry test tube + acetyl
chloride or benzoyl chloride drop by
drop with shaking.
A vigorous reaction takes place
with the evolution of heat and a
solid separates out.
It is a primary amine
or secondary amine.
Carbylamine test
compound + a few drops of
chloroform + Alcoholic KOH
solution. Heat the mixture for few
minutes.
A foul smell of carbylamine
[foul smell is destroyed by
adding con.HCl]
It is a primary amine.
Diazotisation and coupling reaction:
compound is dissolved in excess of
dil.HCl and cooled in ice + ice cold
solution of sodium nitrite.
A pale yellow clear
solution.
Primary amine
Yellow oil Secondary amine
Red oil Tertiary amine
R NH2
Cl
O
R
N
H
O
HCl
R
N
H
R'
R
N
O
R'
or or
Cl
O R
N
H
O
HCl
R NH2
R
N
H
R'
R
N
O
R'
or or
Aliphatic-NH2
CHCl3 3KOH
Aliphatic-NC
3KCl 3H2O
Aromatic-NH2 Aromatic-NC
or or
NH2 N
NaNO2
HCl N
Cl-
R-N2
+
Cl-
or or
R-NH2 (Unstable)
1o
-amine
NH N
NaNO2
HCl
R R
NO
N
NO
RR'
H
N
R'R
or or
2o
-amine

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a) The above pale yellow clear
solution + beta-napthol in NaOH.
A red dye is formed.
Primary amine is
confirmed.
b) The above yellow oil +
con.H2SO4 slowly. Diluted with
water + excess of NaOH
Red solution turns blue or green.
Secondary amine is
confirmed.
N
NaNO2
HCl
R'
R
N
R'
R
ON
N
R'R
R"
N
R'R
R"
N=O
Cl-
3o
-amine
or or
N
N
Cl-
OH
NaOH
HO
N
N
Red-dye

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CHARACTERISTIC REACTIONS OF GROUP IV (A):
REACTION OF CARBOXYLIC ACIDS
Litmus test
compound + water a piece of blue
litmus paper, shaken well.
Blue litmus paper turns red. It is a carboxylic acid.
Bicarbonate test
compound + 5% NaHCO3 solution,
shaken well.
Slow effervescence takes
place with the evolution of
CO2.
It is a carboxylic acid.
Esterification test
compound + 3-4 drops of ethyl
alcohol + 2-3 drops of con.H2SO4.
The mixture is heated and poured
into a beaker containing Na2CO3
solution.
Fruity odour
Carboxylic acid is
confirmed.
Neutral Ferric chloride test
compound + 2cm3
of water +
neutral Fecl3 solution.
Violet colour It is a phenolic acid.
No violet colour It is a carboxylic acid.
R COOH NaHCO3 R COONa CO2 H2O
warm
R COOH H2OC2H5OH R COOC2H5
Con.H2SO4
COOH
OH
FeCl3
COO
O
H
Fe
3
HCl
(Violet color)

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CHARACTERISTIC REACTIONS OF GROUP IV (B):
REACTIONS OF PHENOLS
Ferric Chloride test
+ a few drops of neutral
ferric chloride solution.
Violet or pink
Or
Dirty green solution
It is a phenolic compound
Bromine-water test
compound + bromine water
drop wisely with shaking
Reddish brown color of
bromine is discharged with
white precipitate
It is a phenolic compound
Phthalein fusion test
compound in a dry test tube +
same quantity of phthalic
anhydride + 2 drops of conc.
H2SO4, heat gently. Cooled
and poured into excess of dil
NaOH solution taken in a
beaker.
Pink solution
Or
Yellowish red with green
fluorescence
Or
Blue solution
Phenolic compound is
confirmed
OH
FeCl3
O
Fe
O
O
3HCl
Blue-Violet
OH
Br2 3HBr
OH
BrBr
Br
White Precipitate

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Libermann’s Nitroso reaction
compound + 2 drops of conc.
sulfuric acid+ little of solid
sodium nitrite. Shake
red color which turns to blue
with NaOH
Phenolic compound is
confirmed
OH OH
NO
O
NOH
OH
OH
N
O
ONa
N
O
NaNO2
H2SO4 -H2O
NaOH
Indophenol Sod. salt of
Indophenol

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CHARACTERISTIC REACTIONS FOR V GROUP COMPOUNDS
REACTIONS OF ALDEHYDES AND KETONES
2,4 – Dinitrophenyl hydrazine test
A pinch or a drop of organic compound
+ few drops of 2, 4–dinitrophenyl
hydrazine reagent.
Yellow or orange red
precipitate
It is an aldehyde or
ketone.
Schiff ’s reagent test
+ 2-3 drops of Schiff’s reagent shaken
well.
Pink colored solution. It is an aldehyde.
No pink colored solution. It is a ketone.
Tollen’s reagent test
+ Tollen’s reagent, heat on a water bath
Silver mirror or black
precipitate.
It is an aldehyde
No silver mirror or black
precipitate
It is a ketone
Sodium nitroprusside test
HN
HN
H2N
S
O
OH
S
HO
O
SO3H
NH
NHHN
S
O
S O
HSO3
-
H
R
HO
O
O
H
R
OH
H
O
R2
NH2
H2N
Cl-
NH2
NaHSO3
p-Rosaniline
NH
H2N
NO2
NO2R
O
H
R
O
R'
or
NH
N
NO2
NO2
R H
NH
N
NO2
NO2
R R'
or
H3O+
2,4-dinitrophenylhydrazine
[Ag(NH3)2]OH
(Tollens reagent)
Ag
Silver
mirror
R H
O
R O-
NH4
+
O
Aldehyde carboxylate
salt
3NH3 H2O

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+ few drops of sodium nitroprusside +
NaOH solution.
A red solution It is a ketone
Iodoform reaction
+ iodine solution + excess of NaOH
solution, warm.
Yellow precipitate is
formed or hospital smell
It is a methyl ketone
R CH3
O
R CH2
-
O
Methyl Ketone
NaOH Fe(CN)5NONa2
[Fe(CN)5NO(CH2COR)]2-
Red solution
Sodiumnitroprusside
R CH3
O
R O-
Na+
O
Methyl Ketone
4 NaOH3 I2 CHI3 3 NaI 3 H2O
Iodoform solid
warm

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REACTION OF ESTERS
Phenolpthalein test
compound + 2 drops of NaOH + 1
drop of phenolphthalein,
continuously shaken for few
minutes.
Pink color disappears It is an ester.
Saponification test
Compound + 20% NaOH boiled for
about 10 minutes, cooled + excess
of dil.H2SO4
A white precipitate is formed
It is an ester of aromatic
acid
ONa
O
O
OH
R OR'
O
NaOH
R OH
O
R'OH
O
O
HO
OH
(Pink) (Colorless)
OR'
O
NaOH
ONa
O
R'OH
OH
O
Heat H2SO4

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CHARACTERISTIC REACTIONS FOR VI GROUP COMPOUNDS
REACTIONS FOR HYDROCARBONS
If halogen is absent, reactions for hydrocarbons are carried out. If halogen is present,
raactions for halogenated hydrocarbons are carried out.
Sulphonation
2-3 drops of liquid or a pinch of solid in
the dry test tube + 5cm3
of con.H2SO4
treated with shaking.
Compound dissolves to
form a homogeneous
solution
It is an aromatic
hydrocarbon
Nitration
2-3 drops of con.HNO3 + 2-3 drops of
con.H2SO4 in dry test tube. Add 5 drops
of liquid or a pinch of solid of given
compound. Heated on water bath on a
low flame and poured into ice water.
Yellow solid or yellow oil
is formed
It is an aromatic
hydrocarbon
Con.H2SO4
SO3H
Con. HNO3
Con. H2SO4
NO2
NO2

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REACTIONS OF HALOGENATED HYDROCARBONS
Nitration
2-3 drops of con.HNO3+ 2-3
drops of con.H2SO4 in dry
test tube + 2-3 drops of liquid
or a pinch of solid of given
compound. Heated carefully
with shaking cooled, poured
into ice water.
Yellow oil or yellow solid
separates out.
Aromatic hydrocarbon or
halogenated aromatic
hydrocarbon.
Beilstein’s test
A copper wire is ignited in
non-luminous flame till it
doesn’t impart green color.
Then it is plunged into given
organic compound and again
ignited.
A bluish green color is
imparted to the flame.
Given compound contains
halogen.
Silver nitrate test
compound + alcoholic silver
nitrate. Shake and warm on a
water bath.
Curdy white precipitate
Halogen is in side chain of
hydrocarbon (Aralkyl
halide).
No precipitate
Halogen is on nucleus of
hydrocarbon (Aryl halide)
Con. HNO3
Con. H2SO4
Cl
NO2
Cl
Con. HNO3
Con. H2SO4
NO2
Cl Cl
Cu O2 2 CuO 4R-X 2CuX2
2CuX2 Blue-Gree Light

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CHARACTERISTIC REACTIONS FOR VII GROUP COMPOUNDS
REACTIONS OF ANILIDES
Hydrolysis, diazotization and coupling
compound + few drops of
con.H2SO4 boiled for few
minutes, cooled in ice + ice
cold NaNO2 and ice cold β-
napthol in NaOH
Red dye is formed Anilide is present
Carbylamine test
compound + 2cm3
of 10%
NaOH and heated, cooled+
few drops of chloroform and
it is heated.
A foul smell of carbylamine Anilide is present
N
N
Cl-
OH
NaOH
HO
N
N
Red-dye
HN
O
NH2
H2SO4
NaNO2
HCl
HN
O
NH2
NaOH CHCl3
NaOH
NC

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REACTIONS FOR AMIDES
Alkali test
compound + 10 % NaOH,
boiled and exposed to a wet
red litmus paper to the
vapors.
A glass rod dipped in conc.
HCl is exposed to the vapors.
Pungent smelling gas which
turns red litmus blue.
Dense white fumes are
formed
Amide is present
Alkaline Hydrolysis
compound + 2cm3
of 10%
NaOH and heated, cooled +
dil. HCl
White precipitate Aromatic amide is present
Hydroxamic acid test
compound + H2O2 + FeCl3
solution
Violet color Aromatic amide is present
R NH2
O
NaOH
R ONa
O
NH3
NH2
O
NaOH
ONa
O
NH3
OH
O
H3O+
NH2
O
H2O2
NHOH
O
NHO
O
FeCl3
H2O
Fe
3
Ferric hydroxamate
complex

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REACTIONS OF NITRO COMPOUND
Reduction test
3-4 drops of compound + tin granules + con. HCl boiled with shaking till the yellow
compound dissolves completely to form a colorless solution, filtered and decanted. The clear
solution is divided into two parts
Part I is cooled in ice + ice
cold nitrite solution + β-
napthol in NaOH
A red dye is formed It is a nitro compound
Part II + chloroform +
excess of NaOH, warmed
A foul smell of carbylamine Nitro compound is confirmed
Janowsky’s reaction
compound + acetone +
NaOH solution, shaken well
Pale yellow or colorless
solution
It is mono nitro compound
Pink or blue solution It is dinitro compound
NO2 NH2
Sn
HCl
N
N
Cl-
OH
NaOH
HO
N
N
Red-dye
NaNO2
HCl
NH2
NH2
CHCl3
NaOH
NC
O NaOH O
NO2
NO2
NO2
N
O
O
H
O
Pink
Na

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CHARACTERISTIC DERIVATIVES FOR THE FUNCTIONAL
GROUPS:
PHENOLS
a) Benzoyl derivative :
1 gm of phenol is dissolved in 5ml of 10% NaOH in a test tube + a few drops of
benzoyl chloride, shaken well, filtered, washed and the sample is dried.
OH O C6H5
O
C6H5
O
Cl
b) Bromo derivative:
Dissolve the given compound in 2-3ml of water and add saturated bromine water
dropwise until a solid seperates out. Shaken well, filtered, washed and dried.
AMIDES
Acid Derivative:- Amide + 10% NaOH. Boiled till there is no smell of ammonia, cooled and
acidified with conc. HCl .White precipitate of acid is filtered, washed and dried.
SPECIAL AMIDE
Urea-nitrate Derivative for Urea:- Concentrate solution of urea in small amount of water +
conc. HNO3 with shaking till white precipitate of urea nitrate is formed, cooled filtered and
dried.
H2N
O
NH2
HNO3
H2N
OH
NH2
NO3
OH
Br2 3HBr
OH
BrBr
Br
White Precipitate
NH2
O
NaOH
ONa
O
NH3
OH
O
H3O+

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AMINES
a) Acetyl Derivative:- (For primary and secondary amines): 1 g of amine in a dry test
tube + acetyl chloride or acetyl anhydride drop wise. Vigorous reaction takes place
with the formation of white solid of acetyl derivative. Filtered, washed, and dried.
b) Benzoyl Derivative:- (For primary and secondary amines): Amine in a dry test tube +
benzoyl chloride drop wise. Vigorous reaction takes place with the formation of a
white solid of benzoyl derivative. Filtered, washed and dried
c) Picrate Derivative for Tertiary Amine:- Amine + alcohol +saturated solution of
picric acid in hot alcohol, cooled. The picrate derivative separates. Filtered, washed,
dried.
OH
O2N NO2
NO2
N
R'
R"
R
N R'
R"
R
H
O
O2N NO2
NO2
CARBOXYLIC ACIDS
a) Acetyl Derivative for Phenolic acid:- Compound + acetic acid anhydride and glacial
acetic acid. Heated and poured the mixture into water. Acetyl derivative separates.
Filtered, washed and dried.
COOH
OH
COOH
O
O
O
O
O
OH
O
Cl
O R
N
H
O
HCl
R NH2
R
N
H
R'
R
N
O
R'
or or
R NH2
Cl
O
R
N
H
O
HCl
R
N
H
R'
R
N
O
R'
or or

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b) Bromo Derivative for Phenolic acid:- Phenolic acid + water. Bromine – bromide
solution slowly till color of bromine persists, shaken well. Filtered, washed and dried.
COOH
OH
COOH
OH
Br2
Br
c) Dibromo Derivative for Unsaturated acids:- Compound in a dry test tube +
bromine in acetic acid. Heated for about 5 minutes on a water bath, cool the contents
under the tap water when dibromo derivative separates as a solid. Filter, wash and
dried.
Br2
OH
O
OH
OBr
Br
d) Nitro Derivative for acids:- Compound + 2 cm3
of nitrating mixture (equal volume
of conc. HNO3 + conc. H2SO4) Heated for some time, cooled and poured into water
when nitro derivative separates as a solid. Filtered, washed and dried.
COOH COOH
NO2
Con. H2SO4
Con. HNO3
ALDEHYDES AND KETONES
a) 2,4-Dinitrophenyl hydrazine derivative: compound + a few drops of 2,4-
dinitrophenyl hydrazine when orange red or yellow ppt of 2,4-Dinitrophenyl
hydrazone separates, filtered, washed and dried.
b) Oxime derivatives: Hydroxylamine hydrochloride is dissolved in water. 10% sodium
hydroxide and carbonyl compound dissolved in alcohol are added, the mixture
warmed on a steam bath for 10 min and then cooled in ice. Crystallisation is induced
by scratching the sides of the test tube with a glass rod.
NH
H2N
NO2
NO2R
O
H
R
O
R'
or
NH
N
NO2
NO2
R H
NH
N
NO2
NO2
R R'
or
H3O+
2,4-dinitrophenylhydrazine

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R
O
H
R
O
R'
NH2OH. HCl
R
N
H
R
N
R'
OH
OH
or or H2O
ALCOHOLS
a) Acid derivative for aromatic alcohols: Compound + 5 cm3
of Na2CO3 solution.
Heated carefully+ excess saturated solution of potassium permanganate till pink color
remains filter. Filtrate + dil.H2SO4 till the solution acidic. On cooling solid derivative
separates filtered, washed and dried.
AROMATIC ESTERS
Acid derivative: Compound + 10 cm3
of 20% NaOH solution, Boiled for 10-15 minutes.
Acidified with dil. HCl and cooled. White precipitate of acid derivative separates as a solid.
Filtered, washed and dried.
HYDROCARBONS
Nitro derivative: (For nuclear halogenated hydrocarbons and Mono nitro compounds)
Compound in a dry test tube + 2cm3
of Nitrating mixture (Equal volume of Conc.H2SO4and
Conc.HNO3) Heat for some time. Cooled and poured into water when nitro derivative
separates as a solid filtered, washed and dried.
NO2
NO2
NO2
Con. H2SO4
Con. HNO3
OR'
O
NaOH
ONa
O
R'OH
OH
O
Heat H2SO4
Con. HNO3
Con. H2SO4
Cl
NO2
Cl

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ANILIDES
Bromo derivative: Compound + acetic acid + bromine in acetic acid, shaken well and
poured into water. Bromo derivative separates as a solid. Filtered, washed and dried.
H
N Br2 H
N
OO
Br
CARBOHYDRATES
Osazone derivative: Sugar is heated with acetic acid, sodium acetate and phenylhydrazine
hydrochloride solution. Yellow crystals of Osazone derivative separates out. Filtered, washed
and dried.
CHO
OHH
HHO
OHH
OHH
CH2OH
N
HHO
OHH
OHH
CH2OH
HN
NH2
N NH Ph
NH Ph
Phenylosazone derivative
REFERENCES
1. Comprehensive Practical Organic Chemistry: Qualitative
Analysis- V.K. Ahluwalia and S. Dhingra
2. Practical Organic Chemistry- F. G. Mann and B. C. Saunders
3. Online resources

Semi Micro Qualitative Organic chemistry lab manual

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Semi Micro Qualitative Organic chemistry lab manual