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LUCKNOW PUBLIC SCHOOL, SOUTH CITY HOLIDAY HOMEWORK
Dear Students,
In order to get your practical files ready on time, we are providing you the
Chemistry practical file content. Kindly ensure that you prepare your file in
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LUCKNOW PUBLIC SCHOOL
SOUTH CITY A-BLOCK
PRACTICAL WRITING SKILLS
FOR CLASS XII
SUBJECT-CHEMISTRY
LUCKNOW PUBLIC SCHOOL, SOUTH CITY HOLIDAY HOMEWORK
SALT ANALYSIS
Tests for acid radicals:
Salt or mixture is treated with dil. 42SOH
Acid Radical Observations Confirmatory test
23CO (carbonate) Brisk effervescence
with evolution of
colourless and
odourless gas.
Gas turns lime water milky but milkiness disappears on
passing gas in excess,
22424232 COOHSONaSOHCONa ;
OHCaCOCOOHCa 2milky
32 waterlime
2)( ;
soluble23223 )(HCOCaCOOHCaCO
2S (sulphide) Smell of rotten
eggs SH2( smell)
on heating
Gas turn lead acetate paper black
Sodium carbonate extract *)(SE + sodium nitroprusside –
purple colour, 422422 SONaSHSOHSNa ;
COOHCHPbSPbCOOCHSH 3(black)
232 2)( ;
(purple)idenitropruss sodium
])([])([ 54522 NOSCNFeNaNOCNFeNaSNa
COOCH3
(acetate)
Solution gives
smell of vinegar
Aq. Solution + neutral 3FeCl blood red colour
NaClCOOCHFeFeClCOONaCH 3)(3(red)
33neutral
33
Salt or mixture is treated with conc. 42SOH
Cl (chloride) Colourless
pungent gas giving
white fumes with
aq. OHNH4
(i)Add 2MnO in the same test tube and heat–pale green 2Cl
gas
(ii)S.E.+ 33 AgNOHNO solution –white ppt. soluble in
aq. 3NH
(iii)Chromyl chloride test
3NO (nitrate) Brown pungent
fumes intensified
by the addition of
Cu- turnings.
(i)S.E.+ 33 AgNOHNO yellow ppt. insoluble in aq.
3NH
(ii)Ring test
Specific test in solution:
Sulphate : S.E. add dil. (to decompose 23CO until reaction ceases). Add 2BaCl solution. White ppt.
insoluble in conc. 3HNO , NaClBaSONaSOBaCl 2 ppt.white
442
LUCKNOW PUBLIC SCHOOL, SOUTH CITY HOLIDAY HOMEWORK
Chemical Reactions involved in the tests of Acidic Radicals
Carbonate:
Gas turns lime water milky but milkiness disappears on passing gas in excess,
22424232 COOHSONaSOHCONa ;
OHCaCOCOOHCa 2milky
32 waterlime
2)( ;
soluble23223 )(HCOCaCOOHCaCO
Sulphide:
Gas turns lead acetate paper black
422422 SONaSHSOHSNa ;
COOHCHPbSPbCOOCHSH 3(black)
232 2)( ;
Sodium carbonate extract *)(SE + sodium nitroprusside – purple colour,
(purple)idenitropruss sodium
])([])([ 54522 NOSCNFeNaNOCNFeNaSNa
Chloride:
(i)Add 2MnO in the same test tube and heat–pale green 2Cl gas
HClKHSOSOHKCl 442conc. ; fumes) white(43 ClNHNHHCl
OHClMnClMnOHCl 2222 24
(ii)S.E.+ 33 AgNOHNO solution –white ppt. soluble in aq. 3NH
3 3
white ppt.
KCl AgNO AgCl KNO ; soluble
233 ])([2. ClNHAgNHaqAgCl
(iii) Chromyl- chloride test : Chloride + heat
H conc.)solid( 42722 SOOCrK reddish brown vapours
of chromyl-chloride ).( 22ClCrO Pass these vapours into ,NaOH when yellow 42CrONa solution is formed. On
adding COOHCH3 and 23 )( COOCH Pb, yellow ppt. of lead chromate )( 4PbCrO is formed.
HClKHSOSOHKCl
442conc. ;
OHCrOKHSOSOHOCrK 234conc.
42722 222
OHClCrOHClCrO 2223 22 ;
OHNaClCrONaNaOHClCrO 24222 224
COONaCHPbCrOPbCOOCHCrONa 3 ppt.yellow
42342 2)(
LUCKNOW PUBLIC SCHOOL, SOUTH CITY HOLIDAY HOMEWORK
Nitrate:
34423 HNONaHSOSOHNaNO
fumes brown
2223 244 OHONOHNO ;
OHNONOCuHNOCu 22233 22)(4
Ring test : To water extract (all 3NO are water soluble) add freshly prepared 4FeSO solution and then conc.
42SOH carefully by the side of the test- tube. A dark brown ring of 24
252 ])([ SONOOHFe at the interface
between the two liquids is formed.
34423 222 HNONaHSOSOHNaNO ;
OHNOSOFeSOHSOFeHNO 23424243 42)(3362
OHSONOOHFeNOSOOHFe 224
252462 ])([])([
Tests for basic radicals : Analysis of Basic Radicals
Group Group reagent Basic radical Composition and colour of the precipitate
Zero NaOH 4NH Ammonia gas is evolved
I Dilute HCl Ag 2Pb 2Hg
white:HgCl
white:PbCl
white:
2
2
AgCl
HCl dilute cold
insouble
Chloride
II SH2 in presence of
dilute HCl
2Hg 2Pb 3Bi
2
3
3
2
2
Sn
Sb
As
Cd
Cu
yellow:SnS
brown: SnS
orange:Sb
yellow:As
yellow: CdS
black: CuS
black:Bi
black:PbS
black:
2
32
32
32
S
S
S
HgS
HCl dilute
in insoluble
Sulphides
III OHNH4 in presence of
ClNH4
3
3
3
Al
Cr
Fe
white:Al(OH
green:Cr(OH)
brownreddish
:)(
3
3
3OHFe
OH4NH
in insoluble are Hydroxides
IV
OH
SH
4
2
NH
of presencein
2
2
2
2
Ni
Co
Mn
Zn
black: NiS
black:CoS
buff:MnS
whitegreenish
:ZnS
OH4NH
in insoluble are Sulphides
V
OH
CONH
4
324
NH
of presence
in )(
2
2
2
Ca
Sr
Ba
insoluble are Carbonates
white:CaCO
white:SrCO
white:
3
3
3
BaCO
VI 4NaHPO 2Mg White:)( 44 PONHMg
LUCKNOW PUBLIC SCHOOL, SOUTH CITY HOLIDAY HOMEWORK
Chemical reactions involved in the tests of Basic Radicals
Zero Group
NH 4 (ammonium) : The substance (salt or mixture) when heated with NaOH solution evolves ammonia.
OHNHNaClNaOHClNH 232
When a rod dipped in HCl is brought on the mouth of the test tube, white fumes of ammonia chloride are
formed, fumes White43 ClNHHClNH
To the aqueous solution of ammonium salt when Nessler’s reagent is added, brown coloured precipitate is
formed.
OHKClKI
I
O
NH
Hg
Hg
KOHClNHHgIK 2
ppt.)(Brown basesMillon'of Iodide
2
442 3742
Group I :
When dil. HCl is added to original solution, insoluble chlorides of lead, silver, mercurous mercury are
precipitated.
3223 22)( HNOPbClHClNHPb ; 33 HNOAgClHClAgNO
3223 22)( HNOHgClHClNOHg
Pb2+ (lead)
(i) 2PbCl is soluble in hot water and on cooling white crystals are again formed.
(ii) The solution of 2PbCl gives a yellow precipitate with potassium chromate solution which is insoluble
in acetic acid but soluble in sodium hydroxide.
KClPbCrOCrOKPbCl 2 ppt.yellow
4422 ;
(iii) The solution of 2PbCl forms a yellow precipitate with potassium iodide solution.
KClPbIKIPbCl 22.pptYellow
22
Hg 22 (mercurous)
(i) 22ClHg turns black with OHNH4 , OHClNHClNHHgHgOHNHClHg 242422 2
Black
)(2
(ii) The black residue dissolves in aqua-regia forming mercuric chloride.
ClOHNOClHNOHCl 223 23 ;
222 426)(2 NHClHgClClClNHHg
22 HgClClHg
LUCKNOW PUBLIC SCHOOL, SOUTH CITY HOLIDAY HOMEWORK
Group II : When hydrogen sulphide is passed in acidified solution, the radicals of second group are
precipitated as sulphides.
Pb2+ (lead)
In case the sulphide dissolves in dilute ,3HNO a small part of the solution is taken. Dilute 42SOH is
added. If lead is present, a white precipitate of lead sulphate appears,
3 ppt.)(White
44223 2)( HNOPbSOSOHNOPb
In absence of lead, the remaining solution is made alkaline by the addition of excess of .4OHNH
Bismuth forms a white precipitate of ,)( 3OHBi & Copper forms a deep blue coloured solution while Cadmium
forms a colourless soluble complex,
ppt.White
3)(3)( 343433 NONHOHBiOHNHNOBi ;
solution) blue(deep
nitratecupric e Tetrammin
;4)(])([4)( 22343423 OHNONHCuOHNHNOCu
solution) s(colourles
nitrate cadmium e Tetrammin
4)(])([4)( 22343423 OHNONHCdOHNHNOCd
Cu2+ (copper) : Blue coloured solution is acidified with acetic acid. When potassium ferrocyanide is added a
chocolate coloured precipitate is formed,
442332343 4)(4)()( COONHCHNOCuCOOHCHNONHCu
ppt.Chocolate
4)([])([)(2 3626423 KNOCNFeCuCNFeKNOCu
Cd2+ (cadmium) : SH2 is passed through colourless solution. The appearance of yellow precipitate confirms
the presence of cadmium, 3 ppt.Yellow
3422343 2)()( NHNONHCdSSHNONHCd
Group IIB : In case the precipitate dissolves in yellow ammonium sulphide, the tests of the radicals arsenic,
antimony and tin are performed. The sulphide is treated with concentrated hydrochloric acid. Antimony and
tin sulphide dissolve while arsenic sulphide remains insoluble.
As3+ (arsenic) : The insoluble sulphide is treated with concentrated nitric acid which is then heated with
ammonium molybdate. Yellow precipitate of ammonium arsenomolybdate is formed.
acidArsenic
2243352 5210210 SOHNOAsOHHNOSAs
ppt.Yellow
122112.)(21)(12 2343434342443 OHNONHMoOAsONHHNOMoONHAsOH
LUCKNOW PUBLIC SCHOOL, SOUTH CITY HOLIDAY HOMEWORK
Group III : Hydroxides are precipitated on addition of excess of ammonium hydroxide in presence of
ammonium chloride.
ClNHOHAlOHNHAlCl 4 ppt.Gelatinous
343 3)(3 ;
ClNHOHFeOHNHFeCl 4 ppt.red Brownish343 3)(3
Fe3+ (iron) : The brownish red precipitate dissolves in dilute HCl. The solution is divided into two parts.
Part I : ])([ 64 CNFeK solution is added which forms deep blue solution or precipitate.
OHFeClHClOHFe 233 33)( ;
KClCNFeFeCNFeKFeCl 12])([])([34 bluePrussian
364643
Part II : Addition of potassium thiocyanate solution gives a blood red colouration.
KClCNSFeKCNSFeCl 3)(3colour red Blood
33
Al3+(aluminium) : The gelatinous precipitate dissolves in NaOH ,
OHNaAlONaOHOHAl 2Soluble
23 2)(
The solution is boiled with ammonium chloride when 3)(OHAl is again formed.
2 4 2 3 3NaAlO +NH Cl+H O Al(OH) +NaCl+NH
Group IV : On passing SH2 through the filtrate of the third group, sulphides of fourth group are precipitated.
NiS and CoS are black and insoluble in concentrated HCl
while MnS (buff coloured), ZnS (colourless) are soluble in conc. HCl.
Zn2+ (zinc) : The sulphide dissolves in HCl.
SHZnClHClZnS 222
When the solution is treated with ,NaOH first a white precipitate appears which dissolves in excess of NaOH
NaClOHZnNaOHZnCl 2)(2 ppt.White
22 ; OHZnONaNaOHOHZn 2(Soluble)
222 22)(
On passing SH2 , white precipitate of zinc sulphide is formed NaOHZnSSHZnONa 2 ppt.White
222
Ni2+ (nickel) and Co2+ (cobalt)
The black precipitate is dissolved in aqua- regia.
OHSNONiClHNOHClNis 223 2322263
OHSNOCoClHNOHClCoS 223 4323263
The solution is evaporated to dryness and residue extracted with dilute HCl. It is divided into three parts.
Part I : Add OHNH4 (excess) and dimethyl glyoxime. A rosy red precipitate appears, if nickel is present,
LUCKNOW PUBLIC SCHOOL, SOUTH CITY HOLIDAY HOMEWORK
OHClNH
CHC
CHC
OH
N
N
O
Ni
O
N
N
OH
CCH
CCH
OHNH
NOHCCH
NOHCCH
NiCl 24
3
3
3
3
4
3
3
2 22|
|
|
|2|2
Part II : Add COOHCH3 in excess and .2KNO The appearance of yellow precipitate confirms the
presence of cobalt.
2332 HNOCOOKCHCOOHCHKNO ; KClNOCoKNOCoCl 2)(2 2222
OHNONOCoHNONOCo 232222 )(2)( ; ])([3)( 623232 NOCoKKNONOCo
Group V : Ammonium carbonate precipitates V group radicals in the form of carbonates are soluble in acetic
acid.
OHCOBaCOOCHCOOHCHBaCO 222333 )(2
OHCOSrCOOCHCOOHCHSrCO 222333 )(2
OHCOCaCOOCHCOOHCHCaCO 222333 )(2
Ba2+ (barium) : Barium chromate is insoluble and precipitated by the addition of potassium
chromate solution, COOKCHBaCrOCrOKCOOCHBa 344223 2)(
Sr2+ (Strontium) : Strontium sulphate is insoluble and precipitated by the addition of ammonium
sulphate solution, 43 ppt.White
442423 2)()( COONHCHSrSOSONHCOOCHSr
Ca2+ (calcium) : Calcium oxalate is insoluble and precipitated by the addition of ammonium oxalate.
43 ppt.White
42422423 2)()( COONHCHOCaCOCNHCOOCHCa
Group VI : In the filtrate of V group, some quantity of ammonium oxalate is added as to remove CaBa, and
Sr completely from the solution. The clear solution is concentrated and made alkaline with .4OHNH
Disodium hydrogen phosphate is now added, a white precipitate is formed.
ppt.)(White
phosphateammonium Megnesium
2)( 2444422 OHNaClPONHMgOHNHHPONaMgCl
LUCKNOW PUBLIC SCHOOL, SOUTH CITY HOLIDAY HOMEWORK
Inorganic salt
+ dil. HCl
filter
white residue
(indicates presence of I group)
Pb+2
filtrate
if no ppt. is observed
pass H2S
ppt.
ppt.
ppt.
ppt.
filtrate
filtrate
filtrate
filtrate
(indicates presence of III group)
(indicates presence of II group)
Pb+2,Cu+2,Cd+2
if no ppt. is observed
(i) boil off H2S(ii) add small amount of conc. HNO3 & boil(iii) add NH4Cl (pinch) & then NH4OH(excess)
Al+3, Fe+3
filter
filter
pass H2S
(indicates presence of IV group)Zn+2,Co+2,Mn+2,Ni+2
(i) boil off H2S(ii) add NH4Cl (pinch) & then (NH4)2CO3
(indicates presence of V group)Ba+2,Sr+2,Ca+2
(indicates presence of VI group)
Group Analysis of Basic Radicals
Zero gp. :- heat the salt with a little amount of NaOH, if ammoniacal smell is observed then it indicates presence of Zero Gp. i.e. NH4+ ion.
if no ppt. is observed
if no ppt. is observed
if no ppt. is observed
Mg+2
LUCKNOW PUBLIC SCHOOL, SOUTH CITY HOLIDAY HOMEWORK
Some Sample Experiments on Salt Analysis
EXPERIMENT-1
Aim: - To determine the presence of one acidic & one basic radical in the given inorganic salt.
Apparatus:-
Salt characteristics:-
1. Physical appearance:- 2. Colour:- 3. Odour:- 4. Solubility:-
Analysis of acidic radical:
Experiment Observation Inference
Test for 23CO
Preliminary test:-
Salt + dil. HCl
Brisk effervescence is observed due
to evolution of CO2 gas
23CO suspected
Confirmatory test for the
suspected acidic radical:- The
gas is passed in lime water
Lime water turns milky 23CO confirmed
Analysis of basic radical:
Experiment & Observation Inference
Zero gp.:-
Preliminary test :-NH4
+ salt + alkali (NaOH or
KOH) + heat . Smell of ammonia is evolved
Indicates the presence of
Zero group
Confirmatory test:- Take a cotton plug with a drop
of Nessler’s reagent on it + ammonia gas
It turns brown.
NH4
+ confirmed
RESULT: The given salt contains:
Acidic Radical: 23CO
Basic Radical: NH4
+
LUCKNOW PUBLIC SCHOOL, SOUTH CITY HOLIDAY HOMEWORK
EXPERIMENT-2
Aim: - To determine the presence of one acidic & one basic radical in the given inorganic salt.
Apparatus:-
Salt characteristics:-
1. Physical appearance:- 2. Colour:- 3. Odour:- 4. Solubility:-
Analysis of acidic radical:
Experiment Observation Inference
Test for 24SO
Preliminary & Confirmatory
test for the suspected acidic
radical:-
test:-Salt + dil. HCl + BaCl2
White ppt. due to formation of
BaSO4 which is insoluble in conc.
HNO3
24SO confirmed
Analysis of basic radical:
Experiment & Observation Inference
Zero gp.:-
Preliminary test :-NH4
+ salt + alkali (NaOH or
KOH) + heat .
Smell of ammonia is evolved
Indicates the presence of
Zero gp.
Confirmatory test:- Take a cotton plug with a drop
of Nessler’s reagent on it + ammonia gas
It turns brown.
NH4
+ confirmed
RESULT: The given salt contains:
Acidic Radical: 24SO
Basic Radical: NH4
+
LUCKNOW PUBLIC SCHOOL, SOUTH CITY HOLIDAY HOMEWORK
EXPERIMENT-3
Aim: - To determine the presence of one acidic & one basic radical in the given inorganic salt.
Apparatus:-
Salt characteristics:-
1. Physical appearance:- 2. Colour:- 3. Odour:- 4. Solubility:-
Analysis of acidic radical:
Experiment Observation Inference
Test for COOCH3
Preliminary test:-
Salt + H2O (few drops) + oxalic
acid. rub the paste
Smell of vinegar is observed
Brisk effervescence is observed due
to evolution of CO2 gas
COOCH3 suspected
Confirmatory test for the
suspected acidic radical:-
Salt + dil. HCl + neutral FeCl3
solution
Buff coloured ppt. due to
formation of ferric acetate is
observed
COOCH3 confirmed
Analysis of basic radical:
Experiment & Observation Inference
Zero gp.:-
Preliminary test :-NH4
+ salt + alkali (NaOH or
KOH) + heat
Smell of ammonia is evolved
Indicates the presence of
Zero gp.
Confirmatory test:- Take a cotton plug with a drop
of Nessler’s reagent on it + ammonia gas
It turns brown.
NH4
+ confirmed
RESULT: The given salt contains:
Acidic Radical: COOCH3
Basic Radical: NH4
+
LUCKNOW PUBLIC SCHOOL, SOUTH CITY HOLIDAY HOMEWORK
EXPERIMENT-4
Aim: - To determine the presence of one acidic & one basic radical in the given inorganic salt.
Apparatus:-
Salt characteristics:-
5. Physical appearance:- 6. Colour:- 7. Odour:- 8. Solubility:-
Analysis of acidic radical:
Experiment Observation Inference
Test for COOCH3
Preliminary test:-
Salt + H2O (few drops) + oxalic
acid. rub the paste
Smell of vinegar is observed
Brisk effervescence is observed due
to evolution of CO2 gas
COOCH3 suspected
Confirmatory test for the
suspected acidic radical:-
Salt + dil. HCl + neutral FeCl3
solution
Buff coloured ppt. due to
formation of ferric acetate is
observed
COOCH3 confirmed
Analysis of basic radical:
Experiment & Observation Inference
Zero gp.:-
Preliminary test :-NH4
+ salt + alkali (NaOH or
KOH) + heat
No smell of ammonia is evolved
Indicates the absence of
Zero gp.
Salt + dil. HCl white residue is obtained Indicates the presence of
I gp.
I gp. :- Confirmatory test for Pb+2:- dissolve the white
residue obtained in hot water. Divide it in two parts
To I part: - add KI solution a yellow ppt. is obtained
To II part: - add K2CrO
4 solution a yellow ppt. is
obtained
Pb+2
confirmed
RESULT: The given salt contains:
Acidic Radical: COOCH3
Basic Radical: Pb+2
LUCKNOW PUBLIC SCHOOL, SOUTH CITY HOLIDAY HOMEWORK
EXPERIMENT-5
Aim: - To determine the presence of one acidic & one basic radical in the given inorganic salt.
Apparatus:-
Salt characteristics:-
1. Physical appearance:- 2. Colour:- 3. Odour:- 4. Solubility:-
Analysis of acidic radical:
Experiment Observation Inference
Test for 3NO
Preliminary test:-
Salt + conc. H2SO
4 + Cu turnings
+ heat
Dark brown fumes due to
formation of NO2 evolved
3NO suspected
Confirmatory test for the
suspected acidic radical:-
Salt + dil. H2SO
4 + freshly
prepared FeSO4 solution + conc.
H2SO
4 is added across the walls of
the test tube slowly
A dark brown ring is formed at the
junction of the layers of the acid
and the solution
3NO confirmed
Analysis of basic radical:
Experiment & Observation Inference
Zero gp.:-
Preliminary test :-NH4
+ salt + alkali (NaOH or
KOH) + heat
No smell of ammonia is evolved
Indicates the absence of Zero gp.
Salt + dil. HCl white residue is obtained Indicates the presence of I gp.
I gp. :- Confirmatory test for Pb+2:- dissolve the white residue obtained in hot water. Divide it in two parts
To I part: - add KI solution a yellow ppt. is obtained
To II part: - add K2CrO
4 solution a yellow ppt. is
obtained
Pb+2
confirmed
RESULT: The given salt contains:
Acidic Radical: 3NO
Basic Radical: Pb+2
LUCKNOW PUBLIC SCHOOL, SOUTH CITY HOLIDAY HOMEWORK
EXPERIMENT-6
Aim: - To determine the presence of one acidic & one basic radical in the given inorganic salt.
Apparatus:-
Salt characteristics:-
1. Physical appearance:- 2. Colour:- 3. Odour:- 4. Solubility:-
Analysis of acidic radical:
Experiment Observation Inference
Test for 23CO
Preliminary test:-
Salt + dil. HCl
Brisk effervescence is observed due
to evolution of CO2 gas
23CO suspected
Confirmatory test for the
suspected acidic radical:- The
gas is passed in lime water
Lime water turns milky 23CO confirmed
Analysis of basic radical:
Experiment & Observation Inference
Zero gp.:-
Preliminary test :-NH4
+ salt + alkali (NaOH or
KOH) + heat .
No smell of ammonia is evolved
Indicates the absence of
Zero gp.
I gp. :- Salt + dil. HCl :- No residue was obtained. Indicates the absence of
I gp.
H2S gas is passed to this solution
Yellow Precipitate was obtained
Indicates the presence of
II gp.
II gp. :- Confirmatory test for Cd+2:-
Dissolve the white ppt. in dil. HCl.
Add few drops of K4[Fe(CN)
6] a bluish white ppt. is
obtained
Cd+2
Confirmed
RESULT: The given salt contains:
Acidic Radical: 23CO
Basic Radical: Cd+2
LUCKNOW PUBLIC SCHOOL, SOUTH CITY HOLIDAY HOMEWORK
EXPERIMENT-7 Aim: - To determine the presence of one acidic & one basic radical in the given inorganic salt. Apparatus:- Salt characteristics:-
1. Physical appearance:- 2. Colour:- 3. Odour:- 4. Solubility:-
Analysis of acidic radical:
Experiment Observation Inference
Test for 24SO
Preliminary & Confirmatory
test for the suspected acidic
radical:-
test:-Salt + dil. HCl + BaCl2
White ppt. due to formation of
BaSO4 which is insoluble in conc.
HNO3
24SO confirmed
Analysis of basic radical:
Experiment & Observation Inference
Zero gp.:-
Preliminary test :-NH4
+ salt + alkali (NaOH or
KOH) + heat
No smell of ammonia is evolved
Indicates the absence of
Zero gp.
I gp. :- Salt + dil. HCl :- No residue was obtained. Indicates the absence of
I gp.
H2S gas is passed to this solution
Black Precipitate was obtained
Indicates the presence of
II gp.
II gp. :- Confirmatory test for Cu+2:-
Dissolve the ppt. in 50% HNO3. Boil off H2S gas. Cool
and then add NH4OH in excess to the first part, Deep
blue colouration is observed
Cu+2
Confirmed
Acidify the deep blue solution with acetic acid and then
add potassium ferrocyanide. Chocolate brown ppt. is
formed
Cu+2
Confirmed
RESULT: The given salt contains:
Acidic Radical: 24SO
Basic Radical: Cu+2
LUCKNOW PUBLIC SCHOOL, SOUTH CITY HOLIDAY HOMEWORK
EXPERIMENT-8
Aim: - To determine the presence of one acidic & one basic radical in the given inorganic salt.
Apparatus:-
Salt characteristics:-
1. Physical appearance:-
2. Colour:-
3. Odour:-
4. Solubility:-
Analysis of acidic radical:
Experiment Observation Inference
Test for 24SO
Preliminary & Confirmatory
test for the suspected acidic
radical:-
test:-Salt + dil. HCl + BaCl2
White ppt. due to formation of
BaSO4 which is insoluble in conc.
HNO3
24SO confirmed
Analysis of basic radical:
Experiment & Observation Inference
Zero gp.:-
Preliminary test :-NH4
+ salt + alkali (NaOH or
KOH) + heat
No smell of ammonia is evolved
Indicates the absence of Zero gp.
I gp. :- Salt + dil. HCl :- No residue was obtained. Indicates the absence of gp. I
II gp. :- H2S gas is passed to this solution
No precipitate was obtained
Indicates the absence of gp. II
Add NH4Cl (in pinch) + NH4OH to this solution when a white gelatinous floating precipitate is obtained
Indicates the presence of gp. III
III gp. :- Confirmatory test for Al+3:-
Dissolve the white ppt. in dil. HCl.
Add few drops of blue litmus solution + then add NH
4OH till blue colour develops. Blue ppt. floating in
the colourless solution
Al+3
Confirmed
RESULT: The given salt contains:
Acidic Radical: 24SO
Basic Radical: Al+3
LUCKNOW PUBLIC SCHOOL, SOUTH CITY HOLIDAY HOMEWORK
EXPERIMENT-9
Aim: - To determine the presence of one acidic & one basic radical in the given inorganic salt. Apparatus:- Salt characteristics:-
1. Physical appearance:- 2. Colour:- 3. Odour:- 4. Solubility:-
Analysis of acidic radical:
Experiment Observation Inference
Test for 23CO
Preliminary test:-
Salt + dil. HCl
Brisk effervescence is observed due
to evolution of CO2 gas
23CO suspected
Confirmatory test for the
suspected acidic radical:- The
gas is passed in lime water
Lime water turns milky 23CO confirmed
Analysis of basic radical:
Experiment & Observation Inference
Zero gp.:-
Preliminary test :-NH4
+ salt + alkali (NaOH or KOH)
+ heat .
No smell of ammonia is evolved
Indicates the absence of
Zero gp
I gp. :- Salt + dil. HCl: - No residue was obtained. Indicates the absence of
I gp.
II gp. :- H2S gas is passed to this solution
No precipitate was obtained
Indicates the absence of
II gp.
III gp. :- Add NH4Cl (in pinch) + NH4OH to this solution.
No precipitate was obtained
Indicates the absence of
III gp.
H2S gas is passed to this solution white precipitate
was obtained
Indicates the presence of
IV gp.
IV gp. :- Dissolve the ppt. in HCl.
When the solution is treated with ,NaOH first a
white precipitate appears which dissolves in excess
of NaOH
On passing SH2 , white precipitate is re-formed
Zn+2 is present
RESULT: The given salt contains:
Acidic Radical: 23CO
Basic Radical: Zn+2
LUCKNOW PUBLIC SCHOOL, SOUTH CITY HOLIDAY HOMEWORK
EXPERIMENT-10
Aim: - To determine the presence of one acidic & one basic radical in the given inorganic salt.
Apparatus:-
Salt characteristics:-
1. Physical appearance:- 2. Colour:- 3. Odour:- 4. Solubility:-
Analysis of acidic radical:
Experiment Observation Inference
Test for 23CO
Preliminary test:-
Salt + dil. HCl
Brisk effervescence is observed due
to evolution of CO2 gas
23CO suspected
Confirmatory test for the
suspected acidic radical:- The
gas is passed in lime water
Lime water turns milky 23CO confirmed
Analysis of basic radical:
Experiment & Observation Inference
Zero gp.:-
Preliminary test :-NH4
+ salt + alkali (NaOH or KOH)
+ heat No smell of ammonia is evolved
Indicates the absence of Zero gp.
I gp. :- Salt + dil. HCl: - No residue was obtained. Indicates the absence of I gp.
II gp. :- H2S gas is passed to this solution No precipitate was obtained
Indicates the absence of II gp
III gp. :- Add NH4Cl (in pinch) + NH4OH to this solution. No precipitate was obtained
Indicates the absence of III gp
IV gp. :- H2S gas is passed to this solution No precipitate was obtained
Indicates the absence of IV gp.
V gp. :- Boil off H2S Add NH4Cl (in pinch) + NH4OH to this solution + Add (NH4)2CO3 White ppt. is observed
Indicates the presence of V gp.
The precipitate is dissolved in hot acetic acid solution. To the solution K2CrO4 solution is added
Formation of yellow ppt. confirms the presence of Ba+2 ions.
RESULT: The given salt contains:
Acidic Radical: 23CO
Basic Radical: Ba+2
LUCKNOW PUBLIC SCHOOL, SOUTH CITY HOLIDAY HOMEWORK
EXPERIMENT-11
Aim: - To determine the presence of one acidic & one basic radical in the given inorganic salt.
Apparatus:-
Salt characteristics:-
1. Physical appearance:- 2. Colour:- 3. Odour:- 4. Solubility:-
Analysis of acidic radical:
Experiment Observation Inference
Test for 23CO
Preliminary test:- Salt + dil. HCl
Brisk effervescence is observed due to evolution of CO
2 gas
23CO suspected
Confirmatory test for the suspected acidic radical:- The gas is passed in lime water
Lime water turns milky 23CO confirmed
Analysis of basic radical:
Experiment & Observation Inference
Zero gp.:-
Preliminary test :-NH4
+ salt + alkali (NaOH or KOH)
+ heat No smell of ammonia is evolved
Indicates the absence of Zero gp.
I gp. :- Salt + dil. HCl: - No residue was obtained. Indicates the absence of I gp.
II gp. :- H2S gas is passed to this solution No precipitate was obtained
Indicates the absence of II gp.
III gp. :- Add NH4Cl (in pinch) + NH4OH to this solution. No precipitate was obtained
Indicates the absence of III gp.
IV gp. :- H2S gas is passed to this solution No precipitate was obtained
Indicates the absence of IV gp.
V gp. :- Boil off H2S Add NH4Cl (in pinch) + NH4OH to this solution + Add (NH4)2CO3 White ppt. is observed
Indicates the presence of V gp.
The precipitate is dissolved in hot acetic acid solution. To the solution (NH4)2SO4 solution is added
Formation of yellow ppt. confirms the presence of Sr+2 ions.
RESULT: The given salt contains:
Acidic Radical: 23CO
Basic Radical: Sr+2
LUCKNOW PUBLIC SCHOOL, SOUTH CITY HOLIDAY HOMEWORK
EXPERIMENT-12
Aim: - To determine the presence of one acidic & one basic radical in the given inorganic salt.
Apparatus:-
Salt characteristics:-
1. Physical appearance:- 2. Colour:- 3. Odour:- 4. Solubility:-
Analysis of acidic radical:
Experiment Observation Inference
Test for 23CO
Preliminary test:-
Salt + dil. HCl
Brisk effervescence is observed due
to evolution of CO2 gas
23CO suspected
Confirmatory test for the
suspected acidic radical:- The
gas is passed in lime water
Lime water turns milky 23CO confirmed
Analysis of basic radical:
Experiment & Observation Inference
Zero gp.:-
Preliminary test :-NH4
+ salt + alkali (NaOH or KOH)
+ heat No smell of ammonia is evolved
Indicates the absence of Zero gp.
I gp. :- Salt + dil. HCl: - No residue was obtained. Indicates the absence of I gp.
II gp. :- H2S gas is passed to this solution No precipitate was obtained
Indicates the absence of II gp.
III gp. :- Add NH4Cl (in pinch) + NH4OH to this solution. No precipitate was obtained
Indicates the absence of III gp.
IV gp. :- H2S gas is passed to this solution No precipitate was obtained
Indicates the absence of IV gp.
V gp. :- Boil off H2S Add NH4Cl (in pinch) + NH4OH to this solution + Add (NH4)2CO3 White ppt. is observed
Indicates the presence of V gp.
The precipitate is dissolved in hot acetic acid solution. To the solution (NH4)2C2O4 solution is added
Formation of yellow ppt. confirms the presence of Ca+2 ions.
RESULT: The given salt contains:
Acidic Radical: 23CO
Basic Radical: Ca+2
LUCKNOW PUBLIC SCHOOL, SOUTH CITY HOLIDAY HOMEWORK
ORGANIC FUNCTIONAL GROUP ANALYSIS
EXPERIMENT-13
Aim:- To identify the functional group in the given organic compound[CH3COOH]
Apparatus:-
Procedure:-
Experiment Observation Inference
Test for COOH group :-
Preliminary test:-
Compound + pH paper
Pink colouration is observed
—COOH group
suspected
Confirmatory test for the
suspected functional group:-
Compound + NaHCO3 solution
Brisk effervescence is observed due
to evolution of CO2 gas
—COOH group
confirmed
Result :- The given organic compound contains the …………………….. functional group
EXPERIMENT-14
Aim:- To identify the functional group in the given organic compound[C2H5OH]
Apparatus:-
Procedure:-
Experiment Observation Inference
Test for OH group :-
Preliminary test:- Compound +
pH paper
No significant colour change is
observed
—OH group
suspected
Confirmatory test for the
suspected functional group:-
Compound + NaHCO3 solution
No effervescence is observed due
to evolution of CO2 gas
—OH group
suspected
Confirmatory test for the
suspected functional group :-
Compound + ceric ammonium
nitrate soln
Pink colouration is observed —OH group
confirmed
Result :- The given organic compound contains the …………………….. functional group
LUCKNOW PUBLIC SCHOOL, SOUTH CITY HOLIDAY HOMEWORK
EXPERIMENT-15
Aim:- To identify the functional group in the given organic compound[Phenol]
Apparatus:-
Procedure:-
Experiment Observation Inference
Test for phenolic OH group :-
Preliminary test:-
Compound + pH paper
Significant colour change is
observed
Phenolic —OH
group suspected
Confirmatory test for the
suspected functional group :-
Compound + NaHCO3 solution
No effervescence is observed due
to evolution of CO2 gas
Phenolic —OH
group suspected
Confirmatory test for the
suspected functional group :-
Compound + + neutral FeCl3
solution
Violet colouration is observed Phenolic —OH
group confirmed
Result :- The given organic compound contains the …………………….. functional group
EXPERIMENT-16
Test for acetone [Preparation of iodoform]
Aim:- To identify the functional group in the given organic compound
Apparatus:-
Experiment Observation Inference
Test for acetone:-[preparation of iodoform]
Confirmatory test for the
suspected acidic radical:-
In a test tube take some compound
+ one or two drops of NaOH
solution + iodine solution. Keep
the test tube in the water bath.
Leave it for some time
Formation of yellow ppt [i.e.
formation of iodoform]
Acetone is present
Result :- The given organic compound contains the …………………….. functional group
LUCKNOW PUBLIC SCHOOL, SOUTH CITY HOLIDAY HOMEWORK
EXPERIMENT-17
Aim:- To identify the functional group in the given organic compound
Apparatus:-
By Tollen’s test:-
Result :- The given organic compound contains the …………………….. functional group
Test Observation Inference
Oxidation by Tollen’s reagent (silver mirror test) Tollen’s reagent: - it is an ammoniacal solution of AgNO3.
Sample is dissolved in water and to it 5 ml of Tollen’s reagent is added and then heated on water bath.
Aldehydes on reaction with Tollen’s reagent get oxidized to carboxylic acids thereby reducing the Tollen’s reagent to metallic silver. RCHO + 2 [Ag(NH3)2]
+ + 3OH- RCOO- + 2Ag + 2H2O + 4NH3 (silver mirror)
Aldehydes gives a +ve test with Tollen’s reagent.
LUCKNOW PUBLIC SCHOOL, SOUTH CITY HOLIDAY HOMEWORK
EXPERIMENT-18
PREPARATION OF AZO- DYE
1. Take 10 ml of aniline in a 50 ml beaker.
2. Dissolve it in excess of HCl.
3. Add NaNO2 solution to it.
4. Cool this mixture in a water bath upto a temperature of 0-5 °C.
5. Then add -naphthol solution to it and cool it again upto 0- 5°C.
6. An orange red dye is formed.
REACTION:-
NH2
N NCl+
+optimum acidic
medium ,H + N N
OH
-naphtholbenzene-diazonium chloride
LUCKNOW PUBLIC SCHOOL, SOUTH CITY HOLIDAY HOMEWORK
EXPERIMENT-19
Objective:- to prepare crystals of potash alum.K2SO4.Al2(SO4)3.24H2O
Theory:-
Potash alum is obtained when equimolar quantities of potassium sulphate and aluminium sulphate are mixed and the resulting solution is subjected to crystallization.
Aluminium because of its low density, high tensile strength and resistance to corrosion is widely used for the manufacture of airplanes, automobiles lawn furniture as well as for aluminium cans. Being good conductor of electricity it is used for transmission of electricity. Aluminium is also used for making utensils.
Alums are double sulphates having general formula
X2SO4. M2(SO4)3.24H2O
X = Monovalent cation; M = Trivalent cation
K2SO4.Al2(SO4)3.24H2O – Potash Alum
Na2SO4.Al2(SO4)3.24H2O - Soda Alum
Introduction
Potash alum is used in papermaking, in fire extinguishers, in food stuffs and in purification of water soda alum used in baking powders and chrome alum is used in tanning leather and water proofing fabrics.
Alum is also used as an astringent a substance or preparation that draws together or constricts body tissues and is effective in stopping the flow of blood or other secretions. Alum has also been used by conventional hairdressers for treating shaving cuts.
Apparatus and chemicals:-
Al2(SO4)3.18H2O
K2SO4
Porcelain dish, tripod stand.
Procedure:-
1. Weighed amount of Al2(SO4)3.18H2O is dissolved in water to make its near saturated solution 2. Similarly weighed amount of K2SO4 is dissolved in water to make its near saturated solution 3. The two solutions are mixed in a porcelain dish and then heated on wire gauze and concentrated the
solution to crystallization point. 4. The solution is then left overnight to crystallize 5. The mother liquor is decanted off and the crystals are dried with the help of filter paper
LUCKNOW PUBLIC SCHOOL, SOUTH CITY HOLIDAY HOMEWORK
VOLUMETRIC ANALYSIS
EXPERIMENT-20
Aim: - to prepare 20
Msolution of ferrous ammonium sulphate [Mohr’s salt] and with the help of it find the
molarity and strength of the given KMnO4 solution
THEORY AND EQUATIONS:-
FeSO4.(NH4)2SO4.6H2O FeSO4 + (NH4)2SO4 + 6H2O
Only ferrous sulphate reacts with potassium permanganate
Oxidation of ferrous to ferric:-
[MnO4- + 8H+ + 5e- Mn+2 + 4H2O ] x 2
[ 2Fe+2 Fe2+3 + 2e- ] x 5
2MnO4- +16 H+ +10 Fe+2 2 Mn+2 + 8 H2O + 5 Fe2
+3
Or, 2KMnO4 + 8H2SO4 + 10 FeSO4 K2SO4 +2MnSO4 + 5Fe2(SO4)3 +8H2O
Indicator: - KMnO4 acts as self indicator.
Procedure:-
1. Prepared the 20
M Mohr salt solution
2. Filled the burette with permanganate solution
3. Pipetted out 25 ml of 20
M Mohr salt solution. Added 15-20 ml of H2SO4.
4. Then titration was started by slowly adding drop by drop potassium permanganate solution from burette
5. The pink coloured of the potassium permanganate solution disappeared on reaction with Mohr’s salt. 6. At one point the pink coloured of the potassium permanganate solution did not disappear. 7. This was the end point.
Observations:-
1) Molecular Weight of KMnO4 = 158 gm. 2) Molecular Weight of Mohr’s salt = 392 gm. 3) Weight of Mohr’s salt = 4.9 gm
4) Molarity of Mohr salt solution =20
M
Observation table for titration:-
S.NO. Initial reading of the burette(ml)
Final reading of the burette(ml)
Volume of KMnO4 solution used.
1
2 3
LUCKNOW PUBLIC SCHOOL, SOUTH CITY HOLIDAY HOMEWORK
Calculations:-
4 4 Mohr
4 4
4
KMnO KMnO Mohr
KMnO 4 KMnO
By the Law of equivalence : -
meq. of Oxidising agent = meq. of Reducing agent
meq. of KMnO = meq. of Mohr's salt
Or, N x V (ml) = N x V (ml)
Or, M x n - factor for KMnO x V (mMohr Mohr
4 4 Mohr Mohr
4
KMnO KMnO
l) = M x n - factor for Mohr salt x V (ml)
[SINCE : - N = M x n - factor ]
n - factor for KMnO = 5
n - factor for Mohr = 1
Therefore : - M x 5 x V (ml) = M x 1 x V (ml
Mohr Mohr
4
4
KMnO
KMnO
)
M x 1 x V (ml) M =
5 x V (ml)
……………………………………………………………….
………………………………………………………………
…………………………………………………………….
44 KMnO 4Strength of KMnO solution = M x Molecular mass of KMnO
…………………………………..
Result:-
The molarity of given KMnO4 solution is = ………………………
The strength of given KMnO4 solution is = ………………………
Precautions
The Mohr salt solution should be carefully prepared
Sulphuric acid must be added before starting the titration
Error of parallax should be avoided while taking the burette reading
LUCKNOW PUBLIC SCHOOL, SOUTH CITY HOLIDAY HOMEWORK
EXPERIMENT-21
Aim: - to prepare 40
Msolution of ferrous ammonium sulphate [Mohr’s salt] and with the help of it find the
molarity and strength of the given KMnO4 solution
EXPERIMENT-22
Aim: - to prepare 20
Msolution of oxalic acid and with the help of it find the molarity and strength of the given
KMnO4 solution
THEORY AND EQUATIONS:-
Oxidation of oxalate to carbon dioxide:-
[MnO4- + 8H+ + 5e- Mn+2 + 4H2O ] x 2
[ C2O4-2 2CO2 + 2e- ] x 5
2MnO4- +16 H+ +5 C2O4
-2 2 Mn+2 + 8 H2O + 10CO2
Or, 2KMnO4 + 3H2SO4 + 5 H2C2O4 K2SO4 +2MnSO4 +10CO2 +8H2O
Or, 2KMnO4 + 8H2SO4 + 10 FeSO4 K2SO4 +2MnSO4 + 5Fe2(SO4)3 +8H2O
Indicator: - KMnO4 acts as self indicator.
Procedure:-
1. Prepared the 20
M oxalic acid solution
2. Filled the burette with permanganate solution
3. Pipetted out 25 ml of 20
M oxalic acid solution. Added 15-20 ml of H2SO4.
4. heated the solution to about 60-70°C 5. Then titration was started by slowly adding drop by drop potassium permanganate solution from
burette 6. The pink coloured of the potassium permanganate solution disappeared on reaction with Mohr’s salt. 7. At one point the pink coloured of the potassium permanganate solution did not disappear. 8. This was the end point.
Observations:-
1. Molecular Weight of KMnO4 = 158 gm. 2. Molecular Weight of oxalic acid = 126 gm. 3. Weight of Mohr’s salt = 1.575 gm
4. Molarity of oxalic acid solution =20
M
LUCKNOW PUBLIC SCHOOL, SOUTH CITY HOLIDAY HOMEWORK
Observation table for titration:-
S.NO. Initial reading of the
burette(ml)
Final reading of the
burette(ml)
Volume of KMnO4 solution
used.
1
2
3
Calculations:-
4 4
4
4
KMnO KMnO Oxalic Oxalic
KMnO 4 KMn
By the Law of equivalence : -
meq. of Oxidising agent = meq. of Reducing agent
meq. of KMnO = meq. of Oxalic acid
Or, N x V (ml) = N x V (ml)
Or, M x n - factor for KMnO x V4 Oxalic Oxalic
4 4
O
4
KMnO KMnO Oxalic
(ml) = M x n - factor for Oxalic acid x V (ml)
[SINCE : - N = M x n - factor ]
n - factor for KMnO = 5
n - factor for Mohr = 2
Therefore : - M x 5 x V (ml) = M x 2
Oxalic Oxalic
4
4
Oxalic
KMnO
KMnO
x V (ml)
M x 2 x V (ml) M =
5 x V (ml)
……………………………………………………………….
………………………………………………………………
…………………………………………………………….
44 KMnO 4Strength of KMnO solution = M x Molecular mass of KMnO
…………………………………..
Result:-
The molarity of given KMnO4 solution is = ………………………
The strength of given KMnO4 solution is = ………………………
Precautions
The Mohr salt solution should be carefully prepared.
Sulphuric acid must be added before starting the titration.
Error of parallax should be avoided while taking the burette reading.