SALT ANALYSIS.pdf

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SALT ANALYSIS
Prof.Dr. C.Lingaraj M.Sc.,M.Phil.,M.Ed.,M.Phil.,Ph.D. UGC-SET

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Salt analysis I (LEAD NITRATE)
Aim:
To identify the anion and cation present in the given
simple salt by performing suitable tests
Preliminary tests for anions and cations
S.No. Experiment Observation Inference
1. The colour of the
salt is noted
Colourless May be pb2+
,
Ca2+
, Al3+
, Zn2+
,
Ba2+
,
Sr2+
,Mg2+
,NH4
+
(1)
2. Solubility test: Soluble May be
chloride ,
Iodide,

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A pinch of the salt
is made into
solution with water
Nitrate,
Sulphate, and
ammonium
carbonate.
(2)
3. Action of heat : A
pinch of the salt is
strongly heated in a
dry boiling tube
Reddish brown
vapours
Decrepitation
occurs with
popping sound
May be nitrate
May be lead
nitrate
(3)

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4. Flame test: A
Pinch of the salt is
made into a paste
with con HCl in a
watch glass and is
introduced into a
non luminous
Bunsen flame using
a charred
matchstick
No characteristic
flame is observed
Absence of
Cu2+
, Ba2+
, Sr2+
, Ca2+
.
5. Ash test : A filter
paper is soaked
into a paste of the
salt with dil .HNO3
and cobalt nitrate
No characteristic
coloured ash is
formed
Absence of
Zn2+
, Al3+
,
Mg2+
.

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5
solution and
introduced into the
Bunsen flame and
ignited
6. Action of sodium
hydroxide To 1 ml
of the salt solution
,NaOH is added and
heated
No characteristic
gas is evolved
Absence of
ammonium
salt
II Identification of Anions ( Acid radicals)
7. Action of dil HCl :
To 1 ml of the salt
solution dil . Hcl is
added
No
characteristic
change
Absence of
carbonate
sulphide and
acetate .

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8. Action of sulphuric
acid : To 1 ml of
salt solution
con.sulphuric acid is
added and heated
No characteristic
change
Absence of
chloride
9 Action of sulphuric
acid and
manganese di
oxide : A few drops
is heated with
MnO2 and con.
Sulphuric acid
No characteristic
change
Absence of
chloride,
bromide,
iodide
10. Copper turnings
test: A small
Reddish brown
gas is evolved
Presence of
Nitrate

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quantity of the salt
is heated with
copper turnings and
con sulphuric acid (4)
11 Chromyl Chloride
test : To Pinch of
the salt , potassium
dichromate and
conc. Sulphuric acid
are added and
heated
No orange red
vapours observed
Absence of
chloride
12 Ammonium
Molybdate test: To
No canary yellow
phosphate
Absence of
phosphate

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1 ml of salt solution
con . nitric acid is
added and heated
strongly until fume
ceases . Then
Ammonium
molybdate is added
13. Ethyl Acetate test:
To few drops of the
sodium carbonate
extract, a drop of
con. Sulphuric acid
and 3 ml of ethanol
No pleasant fruity
smell of ester
Absence of
acetate

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are added and
heated in a water
bath . Then the
mixture is poured
into a beaker with
excess of sodium
carbonate
14 Barium Chloride
test: To few drops
of the sodium
carbonate extract ,
add dil HCl and
Barium chloride
No white
precipitate
Absence of
phosphate ,
Carbonate and
sulphate
Sodium Carbonate Extract : Two parts of the sodium
carbonate and one part of the salt are added to distilled water

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and heated. The resultant solution is filtered . The filtrate is
called sodium carbonate extract.
Confirmatory test for anions
1 To few drops of the
extract , dil.
Sulphuric acid is
added and an equal
amount of ferrous
sulphate is added
along the walls of
the test tube
Brown ring at the
junction of the
liquids
Presence of
nitrate is
confirmed
(5)
2. To few drops of the
extract,
diphenylamine
solution is added
Blue colouration is
formed
Presence of
nitrate is
confirmed
(6)

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Identification of basic radicals – Test for cations
Preparation of original salt solution: A little amount of salt is
dissolve in distilled water or by another suitable solvent ie HCl
in hot or cold conditions . This solution is used to identify the
group analysis .
Group Experiment Observation Inference
Zero To 1 ml of the salt
solution , few drops
of Nesslers reagent
and excess of
sodium hydroxide
are added and
heated
No reddish brown
precipitate
Absence of
zero group
ammonium

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First To few drops of the
salt solution dil HCl
is added
White precipitate
is formed
Presence of
lead (first
group ) (7)
Confirmatory test for cations (Basic radicals)
1. To few drops of the
salt solution , 2 ml
of potassium
chromate solution
is added
Yellow precipitate
is obtained
Presence of
lead is
confirmed
(8)
salt solution ,
potassium iodide
solution is added
Yellow precipitate
which dissolve in
water on heating
and reappears on
cooling as shiny
golden
Presence of
lead is
confirmed
(9)

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salt solution dil.
Sulphuric acid is
added
White precipitate
which dissolves in
water on heating
and reappears on
cooling as needle
like crystals
Presence of
lead is
confirmed
(10)
Result : The given salt contains
Acid Radical : nitrate
Basic Radical : lead
Therefore the given salt is lead nitrate .

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Salt analysis II (ALUMINIUM SULPHATE)
Aim:
1 The colour of the
salt is noted
,
Ca2+
, Al3+
, Zn2+
,
Ba2+
,

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Sr2+
,Mg2+
,NH4
+
(1)
2 Solubility test:
A pinch of the salt
is made into
solution with
water
Soluble May be chloride
, Iodide, Nitrate,
Sulphate and
ammonium
carbonate. (2)
3 Action of heat : A
strongly heated in
a dry boiling tube
No characteristic
change
Absence of Zn2+
, Cu2+
, Ni2+
,
Co3
2-
, NO3
-
, I-
,
4 Flame test: A
made into a paste
with con HCl in a
No characteristic
flame is observed
Absence of Cu2+
,
Ba2+
, Sr2+
, Ca2+
.

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watch glass and is
introduced into a
non luminous
Bunsen flame
using a charred
matchstick
5 Ash test : A filter
paper is soaked
into a paste of the
salt with dil .HNO3
and cobalt nitrate
solution and
introduced into
the Bunsen flame
and ignited
No characteristic
coloured ash is
formed
Absence of Zn2+
, Al3+
, Mg2+
,
NH4
+

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6 Action of sodium
hydroxide To 1 ml
,NaOH is added
and heated
No colourless
pungent smelling
gas is evolved
Absence of
ammonium salt
7 Action of dil HCl :
To 1 ml of the salt
added
No
characteristic
change
Absence of
carbonate,
sulphide,
acetate .
acid : To 1 ml of
salt solution
con.sulphuric acid
No characteristic
change
Absence of
chloride
,Bromide,Iodide.

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is added and
heated
acid and
manganese di
oxide : A few
drops of the salt
solution is heated
with MnO2 and
con. Sulphuric acid
No characteristic
change
Absence of
chloride,
bromide, iodide
10. Copper turnings
test: A small
is heated with
copper turnings
No reddish
brown gas is
evolve
Absence of
Nitrate

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and con sulphuric
acid
11 Chromyl Chloride
test : To Pinch of
the salt ,
potassium
dichromate and
conc. Sulphuric
acid are added and
heated
No characteristic
change
Absence of
chloride
12 Ammonium
Molybdate test:
To 1 ml of salt
No canary yellow
phosphate
Absence of
phosphate

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solution con . nitric
acid is added and
heated strongly
until fume ceases .
Then Ammonium
molybdate is
added
To few drops of
the sodium
carbonate extract,
a drop of con.
Sulphuric acid and
No pleasant
fruity smell of
ester
Absence of
acetate

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3 ml of ethanol are
added and heated
in a water bath .
Then the mixture
is poured into a
beaker with excess
of sodium
carbonate
14 Barium Chloride
test: To few drops
of the sodium
carbonate extract ,
add dil HCl and
Barium chloride
white precipitate
insoluble in
dil.Hcl
Presence of
sulphate (3)

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1 To few drops of
the extract , dil.
Acetic acid and
Lead acetate
solution are added
White precipitate
soluble in NaOH
Presence of
sulphate is
confirmed (4)
2. To few drops of
the extract,dil.Hcl
and Barium
chloride solution
are added
White precipitate
insoluble in
dil.Hcl is formed
Presence of
sulphate is
confirmed (5)

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group analysis .
solution , few
drops of Nesslers
reagent and excess
of sodium
hydroxide are
added and heated
No reddish
brown
precipitate
Absence of zero
group
ammonium

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I To few drops of
the salt solution dil
HCl is added
No White
precipitate is
formed
Absence of lead
( I group )
II To a few drops of
the salt solution
add dil.Hcl and
yellow ammonium
sulphide
No Black
precipitate
Absence of lead
or cupric (II
group)
III To a few drops of
the salt solution
add ammonium
chloride and
ammonium
hydroxide
Gelatinous white
precipitate
Presence
ofAluminium
(Al3+
)(III group )
(6)

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1 To few drops of
the salt solution ,
sodium hydroxide
is added
Gelatinous white
precipitate is
obtained
Presence of
Aluminium
(Al3+) is
confirmed (7)
To few drops of
the salt solution,
ammonium
hydroxide solution
and aluminon
reagent are
added
Red lake is
formed
Presence of
Aluminium
(Al3+) is
confirmed (8)
Acid Radical : Sulphate
Basic Radical : Aluminium

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Therefore the given salt is Aluminium Sulphate
Salt analysis III (ZINC SULPHATE)
Aim:

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1 The colour of the
salt is noted
,
Ca2+
, Al3+
, Zn2+
,
Ba2+
,
Sr2+
,Mg2+
,NH4
+
(1)
2 Solubility test:
A pinch of the salt
is made into
Soluble May be chloride
, Iodide, Nitrate,
Sulphate and

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solution with
water
ammonium
carbonate. (2)
3 Action of heat : A
strongly heated in
a dry boiling tube
White turns
yellow
May be Zinc
(Zn2+
)(3)
4 Flame test: A
made into a paste
with con HCl in a
watch glass and is
introduced into a
non luminous
Bunsen flame
No characteristic
flame is observed
Absence of Cu2+
,
Ba2+
, Sr2+
, Ca2+
.

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using a charred
matchstick
5 Ash test : A filter
paper is soaked
into a paste of the
salt with dil .HNO3
and cobalt nitrate
solution and
introduced into
the Bunsen flame
and ignited
Green coloured
ash
Presence of
Zinc ( Zn2+
) (4)
6 Action of sodium
hydroxide To 1 ml
No characteristic
gas is evolved
Absence of
ammonium salt

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,NaOH is added
and heated
7 Action of dil HCl :
To 1 ml of the salt
added
No
characteristic
change
Absence of
carbonate,
sulphide,
acetate .
acid : To 1 ml of
salt solution
con.sulphuric acid
is added and
heated
No characteristic
change
Absence of
chloride
,Bromide,Iodide.

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acid and
manganese di
oxide : A few drops
is heated with
MnO2 and con.
Sulphuric acid
No characteristic
change
Absence of
chloride,
bromide, iodide
10. Copper turnings
test: A small
is heated with
copper turnings
and con sulphuric
acid
No reddish
brown gas is
evolve
Absence of
Nitrate

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11 Chromyl Chloride
test : To Pinch of
the salt ,
potassium
dichromate and
conc. Sulphuric
acid are added and
heated
No orange red
vapours are
evolved
Absence of
chloride
12 Ammonium
Molybdate test: To
1 ml of salt
solution con . nitric
acid is added and
heated strongly
until fume ceases .
No canary yellow
phosphate
Absence of
phosphate

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Then Ammonium
molybdate is
added
To few drops of
the sodium
carbonate extract,
a drop of con.
Sulphuric acid and
3 ml of ethanol are
added and heated
in a water bath .
Then the mixture
is poured into a
beaker with excess
No pleasant
fruity smell of
ester
Absence of
acetate

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of sodium
carbonate
14 Barium Chloride
test: To few drops
of the sodium
carbonate extract ,
add dil HCl and
Barium chloride
white precipitate
insoluble in
dil.Hcl
Presence of
sulphate (5)

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1 To few drops of
the extract , dil.
Acetic acid and
Lead acetate
solution are added
White precipitate
soluble in NaOH
Presence of
sulphate is
confirmed (6)
2. To few drops of
the extract,dil.Hcl
and Barium
chloride solution
are added
White precipitate
insoluble in
dil.Hcl is formed
Presence of
sulphate is
confirmed (7)

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group analysis .
solution , few
drops of Nesslers
reagent and excess
of sodium
hydroxide are
added and heated
No reddish
brown
precipitate
Absence of zero
group
ammonium
I To few drops of
the salt solution dil
HCl is added
No White
precipitate is
formed
Absence of lead
( I group )

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the salt solution
add dil.Hcl and
yellow ammonium
sulphide
No Black
precipitate
Absence of lead
or cupric (II
group)
the salt solution
add ammonium
chloride and
ammonium
hydroxide
No characteristic
change
Absence of
Aluminium (Al3+
)
Fe2+
, Fe3+
( III
group)
IV To a few drops of
the salt solution ,
ammonium
chloride ,
Dirty white
precipitate (ZnS )
is formed
Presence of Zinc
(Zn2+
) ( IV group)
(8)

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ammonium
hydroxide and
yellow ammonium
sulphide are added
1 To few drops of
the salt solution ,
sodium hydroxide
is added
White precipitate
soluble in excess
of NaOH
Presence of Zinc
is confirmed
IV group (9)
2 To a few drops of
the salt solution ,
potassium
ferrocyanide
solution is added
White precipitate
is formed
Presence of Zinc
is confirmed
IV group (10)

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3 Ash test:
A filter paper is
soaked into a
mixture of salt
solution and cobalt
Nitrate solution
and then
introduced into
the Bunsen flame
and ignited
Green ash Presence of Zinc
is confirmed
(11)

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Acid Radical : Sulphate
Basic Radical : Zinc
Therefore the given salt is Zinc Sulphate
Salt analysis IV CALCIUM CARBONATE

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Aim:
1 The colour of
the salt is
noted
, Ca2+
, Al3+
,
Zn2+
, Ba2+
,
Sr2+
,Mg2+
,NH4
+
(1)
2 Solubility test:
A pinch of the
salt is made
into solution
with water
InSoluble May be Sulphide S2-
,
Carbonate CO3
2-
except
ammonium carbonate
(2)

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3 Action of
heat: A pinch
of the salt is
strongly
heated in a
dry boiling
tube
Colourless gas
that turns
lime water
milky
May be carbonate
( Co3
2-
)
(3)
4 Flame test: A
Pinch of the
salt is made
into a paste
with con HCl
in a watch
glass and is
introduced
Brick red Presence of Calcium
(Ca2+)
(4)

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into a non
luminous
Bunsen flame
using a
charred
matchstick
5 Ash test : A
filter paper is
soaked into a
paste of the
salt with dil
.HNO3 and
cobalt nitrate
solution and
introduced
No
characteristic
ash
Absence of Zn2+
,
Al3+
, Mg2+

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into the
Bunsen flame
and ignited
6 Action of
sodium
hydroxide To
1 ml of the
salt solution
,NaOH is
added and
heated
No colourless
pungent
smelling gas
is evolved
Absence of ammonium
salt
7 Action of dil
HCl : To 1 ml
of the salt
Brisk
effervescence
with the
Presence of carbonate
(5)

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solution dil .
Hcl is added
release of a
colourless and
odouless gas
that turns
lime water
milky
8 Action of
sulphuric acid
: To 1 ml of
salt solution
con.sulphuric
acid is added
and heated
NO
characteristic
change
Absence of chloride ,
Bromide and Iodide

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9 Action of
sulphuric acid
and
manganese di
oxide : A few
drops of the
salt solution is
heated with
MnO2 and
con. Sulphuric
acid
NO
characteristic
change
Bromide and Iodide
10. Copper
turnings test:
A small
quantity of
No reddish
brown gas is
evolved
Absence of Nitrate

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the salt is
heated with
copper
turnings and
con sulphuric
acid
11 Chromyl
Chloride test :
To Pinch
of the salt ,
potassium
dichromate
and conc.
No red orange
vapours
Absence of chloride

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Sulphuric
acid are
added and
heated
12 Ammonium
Molybdate
test: To 1 ml
of salt
solution con .
nitric acid is
added and
heated
strongly until
fume ceases .
Then
No canary
yellow
phosphate
Absence of phosphate

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Ammonium
molybdate is
added
13. Ethyl Acetate
test: To few
drops of the
sodium
carbonate
extract, a
No pleasant
fruity smell of
ester
Absence of acetate

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drop of con.
Sulphuric acid
and 3 ml of
ethanol are
added and
heated in a
water bath .
Then the
mixture is
poured into a
beaker with
excess of
sodium
carbonate

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14 Barium
Chloride test:
To few drops
of the sodium
carbonate
extract , add
dil HCl and
Barium
chloride
white
precipitate
soluble in
dil.HCl
Presence of carbonate
(6)

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1 To a few
drops of the
salt solution ,
Barium
chloride
solution is
added
White
precipitate
soluble in dil.
HCl
Presence of Carbonate
is confirmed
(7)
2 To a few
drops of the
salt solution
add
Magnesium
chloride
White
precipitate
soluble in dil.
Hcl
is confirmed
(8)

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group analysis .
Zero To 1 ml of the
salt solution ,
few drops of
Nesslers
reagent and
excess of
sodium
hydroxide are
added and
heated
No reddish
brown
precipitate
Absence of zero group
ammonium

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I To few drops
of the salt
solution dil
HCl is added
No White
precipitate is
formed
Absence of lead ( I
group )
II To a few
drops of the
salt solution
add dil.Hcl
and yellow
ammonium
sulphide
No Black
precipitate
Absence of lead or
cupric (II group)
III To a few
drops of the
salt solution
add
No
characteristic
change
Absence of Aluminium
(Al3+
) Fe2+
, Fe3+
( III
group)

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ammonium
chloride and
ammonium
hydroxide
IV To a few
drops of the
salt solution ,
ammonium
chloride ,
ammonium
hydroxide and
yellow
ammonium
sulphide are
added
No
characteristic
change
Absence of Zinc(Zn2+
) ,
Manganese(Mn2+
)Cobalt
(Co2+
) ,Nickel (Ni2+
)
IV group

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V To a few
drops of the
salt solution,
ammonium
chloride ,
ammonium
hydroxide and
ammonium
carbonate are
added
White
precipitate
May be Barium ,
strontium or Calcium
V group
(9)
For V group, Confirmatory test for cations (Basic radicals)
First by Ba2+
, Sr2+
, Ca2+
.
1 To 1 ml of the
salt solution ,
ammonium
White
precipitate
Presence of
calcium is confirmed
V group

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oxalate
solution is
added
(10)
2 To 1 ml of the
salt solution
potassium
ferrocyanide
is added
White
precipitate
Presence of Calcium is
confirmed
V group
(11)
Acid Radical : Carbonate
Basic Radical : Calcium
Therefore the given salt is Calcium carbonate
Salt analysis V (AMMONIUM CARBONATE)
Aim:

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1 The colour of
the salt is
noted
, Ca2+
, Al3+
,
Zn2+
, Ba2+
,
Sr2+
,Mg2+
,NH4
+
(1)
2 Solubility test:
A pinch of the
salt is made
into solution
with water
Soluble May be chloride,
Bromide, Iodide,
Nitrate, Sulphate and
ammonium carbonate
(2)

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3 Action of
heat: A pinch
of the salt is
strongly
heated in a dry
boiling tube
Colourless gas
that turns lime
water milky
May be carbonate
( Co3
2-
)(3)
4 Flame test:
A Pinch of the
salt is made
into a paste
with con HCl in
a watch glass
and is
introduced
into a non
No
characteristic
flame
Absence of Cu2+
, Ba2+
,
Sr2+
, Ca2+

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luminous
Bunsen flame
using a
charred
matchstick
5 Ash test :
A filter paper
is soaked into
a paste of the
salt with dil
.HNO3 and
cobalt nitrate
solution and
introduced
into the
No
characteristic
ash
Absence of Zn2+
,
Al3+
, Mg2+

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Bunsen flame
and ignited
6 Action of
sodium
hydroxide
To 1 ml of the
salt solution
,NaOH is
added and
heated
A Colourless
pungent
smelling gas is
evolved which
turns red
litmus paper
blue and gives
dense white
fumes with a
rod dipped in
con. Hcl
Presence of
ammonium salt (NH4+
)
(4)

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7 Action of dil
HCl :
To 1 ml of the
salt solution dil
. Hcl is added
Brisk
effervescence
with the
release of a
colourless and
odouless gas
that turns lime
water milky
Presence of
carbonate
(5)
8 Action of
sulphuric acid
: To 1 ml of
salt solution
con.sulphuric
acid is added
and heated
NO
characteristic
change
Bromide and Iodide

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9 Action of
sulphuric acid
and
manganese di
oxide : A few
drops of the
salt solution is
heated with
MnO2 and
con. Sulphuric
acid
NO
characteristic
change
Bromide and Iodide
10. Copper
turnings test:
A small
quantity of the
No reddish
brown gas is
evolved
Absence of Nitrate

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salt is heated
with copper
turnings and
con sulphuric
acid
11 Chromyl
Chloride test :
To Pinch
of the salt ,
potassium
dichromate
and conc.
Sulphuric acid
No red orange
vapours
Absence of chloride

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are added
and heated
12 Ammonium
Molybdate
test: To 1 ml of
salt solution
con . nitric acid
is added and
heated
strongly until
fume ceases .
Then
Ammonium
molybdate is
added
No canary
yellow
phosphate
Absence of phosphate

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13. Ethyl Acetate
test: To few
drops of the
sodium
carbonate
extract, a drop
of con.
Sulphuric acid
and 3 ml of
ethanol are
added and
heated in a
water bath .
No pleasant
fruity smell of
ester
Absence of acetate

67
67
Then the
mixture is
poured into a
beaker with
excess of
sodium
carbonate
14 Barium
Chloride test:
To few drops
of the sodium
carbonate
extract , add
dil HCl and
white
precipitate
soluble in
dil.HCl
Presence of
carbonate
(6)

68
68
Barium
chloride
1 To a few drops
of the salt
solution ,
Barium
chloride
solution is
added
White
precipitate
soluble in dil.
HCl
is confirmed (7)

69
69
2 To a few drops
of the salt
solution add
Magnesium
chloride
White
precipitate
soluble in dil.
Hcl
is confirmed (8)
group analysis .
solution , few
drops of Nesslers
Reddish brown
precipitate
Presence of
ammonium salt
( Zero group)

70
70
reagent and excess
of sodium
hydroxide are
added and heated
(9)
I To few drops of the
salt solution dil HCl
is added
No White
precipitate is
formed
Absence of lead
( I group )
the salt solution
add dil.Hcl and
yellow ammonium
sulphide
No Black
precipitate
Absence of lead
or cupric (II
group)
the salt solution
add ammonium
No characteristic
change
Absence of
Aluminium

71
71
chloride and
ammonium
hydroxide
(Al3+
) Fe2+
,
Fe3+
( III group)
IV To a few drops of
the salt solution ,
ammonium
chloride ,
ammonium
hydroxide and
yellow ammonium
sulphide are added
No characteristic
change
Absence of
Zn2+
,Mn2+
, Co2+
,
Ni2+
( IV group )
V To a few drops of
the salt solution
ammonium
chloride ,
No white
precipitate
Absence of
Barium,
Strontium ,

72
72
ammonium
hydroxide and
ammonium
carbonate are
added
Calcium ( V
Group )
VI To a few drops of
the salt solution
ammonium
chloride ,
ammonium
hydroxide and
disodium hydrogen
phosphate are
added
No White
precipitate
Absence of
Magnesium
(Mg2+
)
( VI group)

73
73
1 To 1 ml of the salt
solution , few
drops of Nessler’s
reagent and excess
of sodium
hydroxide are
added and heated
Reddish brown
precipitate
Presence of
Ammonium is
confirmed
(10)
Result :
The given salt contains
Acid radical : Carbonate
Basic radical : Ammonium

74
74
Therefore the given salt is ammonium carbonate

SALT ANALYSIS.pdf

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