Engg. Chemistry Lab. LM 1st Year

E-Learning Material
on
Engineering Chemistry Practical

of
1st/2nd semester of all Engineering Branches
State Council for Technical Education and

Vocational Training, Odisha
Bhubaneswar-751012
Odisha
SCTE&VT LR Material in Engineering Chemistry Lab 1

E-Learning Material
Engineering Chemistry Practical

of
st nd
1 /2 semester of all Engineering Branches of Diploma courses of
SCTE&VT, Odisha
Contents Written by
Sri. Papun Mirddha, Lecturer in Chemistry, GP,Boudh.
Reviewed and validated by
Sri. Prabodh Kumar Satapathy, Lecturer in Chemistry,

G.P. Bhubaneswar
All rights are reserved by SCTE&VT, Odisha. This material is meant to be used by
students of Diploma Course of SCTE&VT, Odisha, as downloadable from SCTE&VT
website free of cost. This material is not to be treated as Textbook, but be treated as
reference material.
Published by
SCTE&VT, Odisha, Bhubaneswar-12
https://sctevtodisha.nic.in/en/
secretarysctevt@gmail.com,material.sctevt@gmail.com

SYLLABUS
EXPERIMENT CHAPTER
NO.
1 Preparation and Study of Properties of Carbon Dioxide Gas
2 Preparation and Study of Properties of Amonia Gas
3
Crystallization of Copper Sulphate from Carbonate Powder
4
SIMPLE ACID BASE TITRATION
(i) ACIDIMETRY
(ii) ALKALIMETRY
5
TEST FOR ACID RADICALS (KNOWN)
(i) CARBONATE
(ii) SULPHIDE
(iii) CHLORIDE
(iv) NITRATE
(v) SULPHATE
6 TEST FOR BASIC RADICALS (KNOWN)
(i) AMMONIUM
(ii) ZINC
(iii) MAGNESIUM
(iv) ALUMINIUM
(v) CALCIUM
(vi) SODIUM
(vii) POTASSIUM
7 TEST FOR UNKNOWN ACID RADICALS.
8 TEST FOR UNKNOWN BASIC RADICALS.
9 TEST FOR UNKNOWN SALT (COMPOSED OF ONE BASIC AND

ONE ACID RADICALS).

CONTENTS
SL. NO SUBJECT PAGE NO
1. PREPARATION AND STUDY OF PHYSICAL AND 3 to 6
CHEMICAL PROPERTIES OF CO2 GAS.
2. PREPARATION AND STUDY OF PHYSICAL AND 7 to 10
CHEMICAL PROPERTIES OF NH3 GAS.
3. CRYSTALLIZATION OF COPPER SULPHATE FROM 11 to 14
COPPER CARBONATE.
4. SIMPLE ACID BASE TITRATION
(i) ACIDIMETRY 15 to 18
(ii) ALKALIMETRY 19 to 22
5. TEST FOR ACID RADICALS (KNOWN) 23 to 27
(i) CARBONATE
(ii) SULPHIDE
(iii) CHLORIDE
(iv) NITRATE
(v) SULPHATE
6. TEST FOR BASIC RADICALS (KNOWN) 28 to 35
(i) AMMONIUM
(ii) ZINC
(iii) MAGNESIUM
(iv) ALUMINIUM
(v) CALCIUM
(vi) SODIUM
(vii) POTASSIUM
7. TEST FOR UNKNOWN ACID RADICALS. 36 to 38
8. TEST FOR UNKNOWN BASIC RADICALS. 39 to 45
9. TEST FOR UNKNOWN SALT (COMPOSED OF ONE BASIC 46 to 53
AND ONE ACID RADICALS).

EXPERIMENT NO-01
AIM OF THE EXPERIMENT:

Preparation and study of physical and chemical properties of carbon dioxide gas.
APPARATUS REQUIRED:
1.Woulf’sbottle. 4. Rubbercork.
2.Thistlefunnel. 5. Gas jar withlid.
3. Deliverytube. 6. Few testtubes.
CHEMICALS REQUIRED:
1.Marblechips (CaCO3). 4.Magnesiumribbon.
2.Dil.Hydrochloricacid (HCl). 5.Limewater.
3.Litmuspaper. 6.Phenolphthaleinsolution.
THEORY:
In laboratory carbon dioxide gas is prepared by the action of dilute hydrochloric acid (HCl) upon
marble chips (CaCO3) in a woulf’s bottle. It is collected by upward displacement of air. Carbon
dioxide is heaviour in nature.
CHEMICAL EQUATIONS:
CaCO3 +2HCl →CaCl2 +H2O+CO2
LABORATORY DIAGRAM:
Fig 1.1 Laboratory Preparation of carbon dioxide gas.

PROCEDURE:
1. Take a woulf’s bottle fitted with rubber cork, thistle funnel and delivery tube. Examine thatitis
perfectly airtight. In case of air leakage, use melted paraffin wax or grease.
2. Introduce few small marble chips into the woulf’s bottle by opening one ofitsmouths.
3. Nowpoursomewaterintothewoulf’sbottlethroughthethistlefunnelsoastocover the marble chips.
4. Insert the thistle funnel more into the woulf’s bottle such that its extremeendremainsinside the
water.
5. Now add little quantity of the dil. Hydrochloric acid through the thistle funnel. Do not add
excess amount of acid at a time to exhaust the marble chips before the experiment iscompleted.
6. Then collect the carbon dioxide gas in the gas jar by upward displacement of air. Test the
collected gas in the jar by showing a burning splinter at the mouth of gasjar.
7. Study the properties of carbon dioxide gas by collecting the gas in different test tubes.
OBSERVATION:
PHYSICAL PROPERTIES
SL. EXPERIMENT OBSERVATION INFERENCE
1. Observe the colour ofthe gas
2. Observe the odour of the gas
3. Enter a glowingsplinter
into a test tube full of CO2gas.
4. Invert the test tube full of CO2 gas

over another empty test tube
containing air. Then add little lime to
the testtube containing air initially.

5. Collect the gas in a test tube half-
filled with water. Shake the test tube
vigorously by putting the thumb at its
mouth and remove the thumb and
observe the level/volume of waterin
the test tube.
CHEMICAL PROPERTIES
SL EXPERIMENT OBSERVATION INFERENCE

NO
1 A piece of moist blue

litmus paper is shown to the gas.
2. Pass the CO2 gas through 2-3 ml of

dilute solutions of sodium hydroxide
(NaOH) containing one dropof
phenolphthaleinsolution.
3. a) Pass the gas throughlime water.
b) Pass the gas in excess.
c) Boil thesolution.
4. Introduce a burning magnesium
ribbon into a test tube /gas jar
containingcarbondioxide gas.
SAFTY AND PRECAUTION:

1. The fittings should beairtight.
2. The end of thistle funnel must be remaining deep inside thesolution.
3. The shorter end of the delivery tube should remain above the surface of the solutionin
the woulf’s bottle.
4. The longer end of the delivery tube must reach the bottom of the gasjar.
5. Addition of excess of dil. hydrochloric acid should beavoided.
6. The gas should be collected after removing air from theapparatus.

ASSIGNMENT QUESTIONS:
(1) What are the apparatus required for this experiment?
(2) Write the chemical formula of marble chip.
(3) Can we use CaCO3 powder for preparation of CO2 gas?
(4) Why marble chips are used instead of CaCO3 powder?
(5) Write the chemicals used for preparation of CO2 gas.
(6) How can you prepare dilute HCl?
(7) Hydrochloric acid is a strong or weak acid? Give reason.
(8) Explain the acidic nature of CO2 gas?
(9) What happens when CO2 gas is passed through alkaline phenolphthalein solution?
10. What happens when moist blue and red litmus papers are shown to CO2 gas?
How CO2 gas is collected?
11.What are the apparatus required for preparation of CO2 gas?
12.How can you prepare CO2 gas in laboratory?
13. Why moist blue litmus paper turns red on exposure to CO2 gas?
14.Write two methods of preparation of CO2 gas.
15.What happens when a burning match stick is introduced into a jar containing CO2 gas?
16 .What happens when methyl orange indicator is added to aqueous solution of CO2 gas?
17.What happens when CO2 gas is passed through lime water first in less amount and then
in excess?
18.Write the reactions involved between CO2 gas and lime water.
19.What is the formula of lime water?
20. Why lime water turns milky when less amount of CO2 gas is passed through it? Give
Equation.
21. Why milky colour disappears on passage of excess CO2 gas through lime water? Give
Equation.
22.What happens when colourless Ca(HCO3)2 solution will be warmed strongly? Give
Equation.
23.What happens when a burning magnesium is introduced into gas jar containing CO2
gas? Give Equation.
24.Write two uses of CO2 gas.
25.What is dry ice?
26.How can you test that CO2 gas is heavier than air?
27.Can sulphuric acid (H2SO4) be used in place of HCl for preparation of CO2 gas?
28.What type of bonding is present in CO2 ?
29.Why smaller pieces of marble chips are required?
30.Why the thistle funnel is inserted deep to the bottom of the Woulfe’s bottle?
31.How can you test the solubility of CO2 gas?

EXPERIMENT NO-02
Preparation and study of properties of NH3 gas.
APPARATUS REQUIRED:
1.Hard glass test tube
2.Delivery tube
3.Gas jar
4.Card cover
5.Glass jar containing CaO (quick lime)
6.Bunsen burner
7.Rubber cork
8.Clamp stand
CHEMICALS REQUIRED:
1. Solid Ammonium Chloride, NH4Cl
2. Anhydrous Calcium Hydroxide, Ca(OH)2 or Calcium Oxide (CaO)
THEORY:
Ammonia gas is prepared in laboratory by heating the mixture of ammonium Chloride (NH4Cl) &
Calcium Hydroxide, Ca(OH)2 paste in 1:3 ratio by weight. The reaction proceeds as:
The gas so formed is collected in the gas jar by downward displacement of air because
ammonia gas is lighter than air.The gas cannot be collected under water because it is highly
soluble in water. Ammonia gas is dried by passing it through the glass bottle containing CaO.
DIAGRAM:
Fig 2.1 Laboratory preparation of Ammonia Gas.

PROCEDURE:
1.Take a hard glass test tube with rubber cork and deliverytube.
2.Mix 1:3 ratio of ammonium chloride and calcium hydroxide and place the mixture into the
testtube.
3. Tilt the test tube at 30 degree angle and clamp it to thestand.
4.Attach the rubber cork to the test tube along with delivery tube connected at one end of the
test tube and the other end connected to the glass jar containing CaO. The quicklime is present
so as to absorb moisture present in the ammonia gas.
5.Make sure that all the connections are airtight to prevent leakage of ammonia gas.
6.Now carefully and gently heat the mixture in the testtube.
7.Then collect the ammonia gas in the gas jar by downward displacement ofair.
OBSERVATION:
PHYSICAL PROPERTIES
1 Color of the gas
2 Odour of the gas
3 Collect the gas in a test tube half-

filled with water. Shake the test tube
vigorously by putting the thumb at its
mouth and remove the thumb and
observe the volume of water in the
test tube.
CHEMICAL PROPERTIES
1 Show a piece of moist red litmus

paper to the gas.

2 Pass the gas into the test tube
containing copper sulphate solution
for short timeat first and then in
excess.
3 Pass the gas into the test tube

containing ferric chloride solution.
4 Pass the ammonia gas into the test

tube containing Nessler’s reagent.
CONCLUSION:
Ammonia gas is prepared at laboratory by using ammonium chloride (NH4Cl)&Calcium
hydroxide (Ca(OH)2). Ammonia gas is basic in nature. It is highly soluble in water.
SAFETY MEASURES:
1.The apparatus must be airtight.
2. The hard glass test tube should be fixed in inclined position towards its mouth in order to
prevent crack in it.
3. Heat should be provideduniformly.
4. The gas jar should bedried.

(1) Write the principle of preparation of ammonia gas in laboratory?
(2) What is the principle of collection of ammonia gas?
(3) Write the apparatus required for preparation of ammonia gas?
(4) What are the chemicals required for ammonia gas?
(5) While clamping the hard glass test tube, its mouth is present slightly downward. Why?
(6) Write the physical properties of ammonia gas?
(7) What is the odour of ammonia gas?
(8) What happens when a glass rod dipped in conc HCl is shown to the ammonia gas?
(9) What happens when a test tube filled with ammonia gas is inverted into a trough of water?
(10) Explain a test to show that ammonia is lighter than air?.
(11) Which compound is required to dry ammonia gas?
(12) Why conc. Sulphuric acid is not used to dry ammonia gas ?
(13) Write two tests to show that ammonia is alkaline in nature?
(14) What happens when ammonia gas is passed through Nessler’s reagent? Give equation
?
(15) What happens when ammonia gas is passed through ferric chloride solution? Give
equation?
(16) Ammonia gas has rotten egg / pungent/ irritating/ sweet odour.
(17) Ammonia is sparingly / insoluble / highly soluble in water?
(18) What happens when ammonia gas is passed through copper sulphate solution in small
quantities?
(19) What happens when ammonia gas is passed through copper sulphate solution in
excess?
(20) Ammonia gas turns blue litmus to red / red litmus to blue?
(21) Write the uses of ammonia gas?
(22) What happens when ammonia gas is passed through phenolphthalein solution?
(23) What is the combustibility property of ammonia?
(24) Can NaOH or KOH be used in place of CaO or Ca(OH)2 for preparation of ammonia?
(25) What is that compound (brown precipitate) which forms when ammonia gas is passed
through nessler’s reagent?

EXPERIMENT NO- 03

Crystallization of copper sulphate from copper carbonate.
APPARATUS REQUIRED:
1.Beaker
2.Funnel
3.Glass rod
4.Porcelain basin
5.Tripod stand
6.Wire gauze
7.Bunsen burner
8.Filter paper
9.Filter stand
CHEMICALS REQUIRED:
1.Copper carbonate(CuCO3)
2.Dilute sulphuric acid(H2SO4)
THEORY:
Copper carbonate reacts with dilute sulphuric acid to form soluble copper sulphate with
evolution of carbon dioxide gas. The resulting solution is concentrated by evaporation till the
point of crystallization is reached and then cooled to get crystals of copper sulphate
pentahydrate (CuSO4.5H2O) called blue vitriol.
(Blue vitriol)
Fig 3.1 Filtration

Fig 3.2 Crystallization of copper sulphate .
Procedure :- The preparation of Copper Sulphate crystals from Copper Carbonate involves
following steps.
(A) Preparation of Saturated solution :-

 Take about 20 ml of dilute Sulphuric acid in a beaker.
 Add supplied Copper Carbonate (CuCO3) power gradually to this acid in small
quantities with constant stirring.
 Continue addition of the of the powder till a small quantity of Copper Carbonate
(CuCO3) is left behind.
 Heat the resulting solution slightly to expel the dissolved CO2 gas.
 Take the filter paper and four fold it.
 Prepare a cone of filter paper by taking three folds in one side and one fold in the
other side.
 Take a funnel and insert the cone made by the filter paper in to it.
 Filter the solution from beaker to the porcelain basin .
 The solution must be transfered from the beaker to the filter paper cone slowly
with the help of a glass rod.
 Wash the insoluble component present in the cone with the distilled water so as
to make it free from soluble component.
(B ) Concentrating the Filtrate :-
 Evaporate the filtrate in the porcelain basin with constant stirring.

 Continue the process of evaporation till a drop of the liquid solution forms crystals on the
tip of glass rod when blown on it. This state is termed as Crystallisation point.
( C) Crystallisation :-
 Cool the hot solution ( after reaching crystallisation point ) slowly in air to start the
process of crystallisation.
 If required, keep the hot porcelain basin containing the solution over a beaker full of
water for quicker cooling.

 If required, keep the hot porcelain basin containing the solution over a beaker full of
water for quicker cooling.
( D ) Drying and Crystals :-
 Decant off the saturated mother liquor present over the crystals after the crystallisation
is over.
 Transfer the deep blue crystals present in the porcelain basin to a filter paper and
spread to dry.
Precautions :-
 Minimum amount of dilute sulphuric acid (H2SO4) should be used to prepare the solution
.
 The solution should be slightly acidic , other wise the salt may get hrdrolysed
 The solution should not be heated beyond crystallisation point.
 The concentration of solution must be carried with constant stirring
 Crystals should never be dried by heating.
RESULT:
Color : ……….
Shape:………
Yield: ………. gm

1. Define crystallisation.
2. Define solubility.
3. Define filtration.
4. Why the solution is not concentrated or heated to dryness during crystallisation?
5. What is decantation?
6. Decantation and filtration which is a better process and why?
7. Why the saturated solution be cooled slowly?
8. What is blue vitriol?
9. What are hydrates?
10. What are anhydrous salts?
11. What is seeding ?
12. Aqueous solution of Copper Sulphate solution acidic or basic or neutral?
13. What is efflorescence?
14. What is the colour and structure of anhydrous Copper Sulphate ?
15. Why excess H2SO4 acid is not used for dissolving CuCO3 powder ?
16. What is crystallisation point ?
17. Define mother liquor .
18 Write the reaction between anhydrous CuCO3 and dilute H2SO4 .
19 Why the CuSO4 solution be prepared slightly acidic ?
20 Can CuO be used instead of CuCO3 powder for preparation of blue vitriol? If yes, then
write the reaction.
21 Write two uses of CuSO4.5H2O ?
22 Mention two other salts which can be prepared by this method .
23 Why a glass rod is used to transfer the solution from beaker to the filter paper cone in
the funnel?
24 How can one check the crystallisation point ?
25 How a filter paper cone be prepared?

EXPERIMENT NO- 4(i)

Acidimetry: To determine the strength of unknown acid using standard alkali..
APPARATUSREQUIRED:
1.Burette (50 ml.)
2.Burette Stand with clamp
3.Pipette (10 ml.)
4.Conical flask (100ml.)
5.Measuring flask (250ml.)
6.Glazed porcelain
CHEMICALS REQUIRED:
1.Acid Solution (Unknown Strength)
2.N/10 Alkali Solution (Known Strength)
3.Indicator: Methyl Orange
THEORY:
A known volume of standard alkali solution is titrated against the supplied acid solution
of unknown strength in the presence of methyl orange indicator till the colour just changes from
pale yellow/ straw yellow to light pink. The volume of the acid required for neutralization is
determined. Knowing the volume of both the solutions and the strength of alkali, the strength of
acid solution can be calculated by using the principle of equivalency.
NaVa=NbVb
Where,
Na=Normality of the acid solution.
Va=Volume of acid solution.
Nb=Normality of alkali solution.
Vb=Volume of alkali solution.

PROCEDURE:
1.Wash the burette, pipette and conical flask thrice with tap water and then rinse with distilled
water.
2.Rinse the burette thrice with a few ml. of the given acid solution and reject the washings.
3.Fill the burette with the given acid solution to a convenient level without air bubbles. 4.Remove
air bubble (if any) present in it.
5.Rinse the pipette with the alkali solution thrice and reject the washing.
6. Pipette out 10 ml. of alkali solution is into the conical flask.
7.After transferring the acid solution, touch the tip of the pipette to the inner side of the conical
flask thrice. Wash the inner sides of the conical flask with a little distilled water.
8.Add one drop of methyl orange indicator to it. Keep the conical flask over a white glazed
porcelain tile under the burette.
9.Note the initial burette reading avoiding parallax error.
10.Carry out titration by running alkali from the burette with constant stirring till the colour of the
solution just changes from colorless to light pink.
11. Note the final burette reading. Repeat the titration till three concordant values are obtained.
Fig 4.1 Titration

OBSERVATION:
No of Volume of Initial burette Final burette Difference Concordant
Observations alkali (ml.) reading (ml.) reading (ml.) (ml.)
CALCULATION:
We know that NaVa=NbVb
Where,
Na=Normality of acid solution
Va=Volume of acid solution consumed
Nb=Normality of alkali solution
Vb=Volume of alkali solution
Na=NbVb/Va= --------- N/10
CONCLUSION:
From the above titration the strength of unknown acid solution is found to be --------.
PRECAUTIONS:
1.Care should be taken while handling the acid and base.
2.Always rinse the burette and the pipette with the solution which is to be taken in them.
3.Remove the air gap if any, from the burette before titration.
4.Never forget to remove the funnel from the burette before noting the initial reading of the
burette and ensure that no drop is hanging from the nozzle.
5.Always read the lower meniscus for all transparent solutions and upper meniscus for the
coloured solutions.
6.Never use burette and pipette with a broken nozzle.
7.Never suck a strong acid or an alkali with the pipette, use pipette bulb.
8.Always keep the lower end of the pipette dipped in the liquid while sucking the liquid

(1) What do you mean by volumetric analysis?
(2) What is titration?
(3) Define titrant and titrate?
(4) What are acidimetry and alkalimetry ?
(5) Define a standard solution?
(6) What do you mean by concentration / strength of solutions?
(7) Define an indicator?
(8) Name few indicators which are used during acid – base titration?
(9) Define gram equivalent weight and gram equivalent?
(10) What is molality and normality?
(11) 10 grams of caustic soda is how much gram equivalents?
(12) What is the principle of titration?
(13) Why rinsing is necessary?
(14) Why conical flask is not rinsed with acid or alkali?
(15) What is an anti parallax card?
(16) Why one should not hold the pipette from its bulb?
(17) Why the last drop of the solution be not blown from its bulb?
(18) Why one or two drops of indicator should always be used?
(19) Define the end point or neutralisation point?
(20) How can you detect the neutralisation point?
(21) Why mostly decinormal(N/10) solutions are used rather than normal(N) or
centinormal(N/100) solutions?
(22) Which solutions are required to rinse the burette and pipette?
(23) To prepare 2 litres of solution, how much amount of sodium carbonate is
required?
(24) Why presence of air bubbles is not preferred in the burette while filling the acid
solution?
(25) Why stirring of conical flask and slow addition of acid is required?
(26) What are the colours of methyl orange and phenolphthalein solutions in acidic,
alkali and neutral mediums?
(27) How the strength of the solution can be determined?

EXPERIMENT NO- 4(ii)

Alkalimetry: To determine the strength of unknown alkali using standard acid..
APPARATUSREQUIRED:
1.Burette (50 ml.)
2.Burette Stand with clamp
3.Pipette (10 ml.)
4.Conical flask (100ml.)
5.Measuring flask (250ml.)
6.Glazed porcelain
CHEMICALS REQUIRED:
1. N/10 Acid Solution (known Strength)
2. Alkali Solution (unknown Strength)
3.Indicator: Methyl Orange
THEORY:
A known volume of standard alkali solution is titrated against the supplied acid solution
of unknown strength in the presence of methyl orange indicator till the colour just changes from
pale yellow/ straw yellow to light pink. The volume of the acid required for neutralization is
determined. Knowing the volume of both the solutions and the strength of alkali, the strength of
acid solution can be calculated by using the principle of equivalency.
NaVa=NbVb
Where,
Na=Normality of the acid solution.
Va=Volume of acid solution.
Nb=Normality of alkali solution.
Vb=Volume of alkali solution.

PROCEDURE:
1.Wash the burette, pipette and conical flask thrice with tap water and then rinse with distilled
water.
2.Rinse the burette thrice with a few ml. of the given acid solution and reject the washings.
3.Fill the burette with the given acid solution to a convenient level without air bubbles. 4.Remove
air bubble (if any) present in it.
5.Rinse the pipette with the alkali solution thrice and reject the washing.
6. Pipette out 10 ml. of alkali solution is into the conical flask.
7.After transferring the acid solution, touch the tip of the pipette to the inner side of the conical
flask thrice. Wash the inner sides of the conical flask with a little distilled water.
8.Add one drop of methyl orange indicator to it. Keep the conical flask over a white glazed
porcelain tile under the burette.
9.Note the initial burette reading avoiding parallax error.
10.Carry out titration by running alkali from the burette with constant stirring till the colour of the
solution just changes from colorless to light pink.
11. Note the final burette reading. Repeat the titration till three concordant values are obtained.
Fig 4.1 Titration

OBSERVATION:
No of Volume of Initial burette Final burette Difference Concordant
Observations alkali (ml.) reading (ml.) reading (ml.) (ml.)
CALCULATION:
We know that NaVa=NbVb
Where,
Na=Normality of acid solution
Va=Volume of acid solution consumed
Nb=Normality of alkali solution
Vb=Volume of alkali solution
Na=NbVb/Va= --------- N/10
CONCLUSION:
From the above titration the strength of unknown acid solution is found to be --------.
PRECAUTIONS:
1.Care should be taken while handling the acid and base.
2.Always rinse the burette and the pipette with the solution which is to be taken in them.
3.Remove the air gap if any, from the burette before titration.
4.Never forget to remove the funnel from the burette before noting the initial reading of the
burette and ensure that no drop is hanging from the nozzle.
5.Always read the lower meniscus for all transparent solutions and upper meniscus for the
coloured solutions.
6.Never use burette and pipette with a broken nozzle.
7.Never suck a strong acid or an alkali with the pipette, use pipette bulb.
8.Always keep the lower end of the pipette dipped in the liquid while sucking the liquid

(1) What do you mean by volumetric analysis?
(2) What is titration?
(3) Define titrant and titrate?
(4) What are acidimetry and alkalimetry ?
(5) Define a standard solution?
(6) What do you mean by concentration / strength of solutions?
(7) Define an indicator?
(8) Name few indicators which are used during acid – base titration?
(9) Define gram equivalent weight and gram equivalent?
(10) What is molality and normality?
(11) 10 grams of caustic soda is how much gram equivalents?
(12) What is the principle of titration?
(13) Why rinsing is necessary?
(14) Why conical flask is not rinsed with acid or alkali?
(15) What is an anti parallax card?
(16) Why one should not hold the pipette from its bulb?
(17) Why the last drop of the solution be not blown from its bulb?
(18) Why one or two drops of indicator should always be used?
(19) Define the end point or neutralisation point?
(20) How can you detect the neutralisation point?
(21) Why mostly decinormal(N/10) solutions are used rather than normal(N) or
centinormal(N/100) solutions?
(22) Which solutions are required to rinse the burette and pipette?
(23) To prepare 2 litres of solution, how much amount of sodium carbonate is
required?
(24) Why presence of air bubbles is not preferred in the burette while filling the acid
solution?
(25) Why stirring of conical flask and slow addition of acid is required?
(26) What are the colours of methyl orange and phenolphthalein solutions in acidic,
alkali and neutral mediums?
(27) How the strength of the solution can be determined?

EXPERIMENT NO-5

Test for carbonate, sulphide, chloride, nitrate, sulphate radicals (Known)
APPARATUS REQUIRED:
1. Test tube holder
2. Watch Glass
3. Test tubes
4. Bunsen Burner
CHEMICALS REQUIRED:
1.Given salts
2.Various Reagent
3. Litmus paper
THEORY AND PROCEDURE:

TEST FOR ACID RADICALS:
Test for Carbonate (CO32-):
EXPERIMENT OBSERVATION INFERENCE

1.Take 2 ml of dil. HCl or dil. 1. 1.Effervescences takes 1.It may be CO2 from CO32-
H2SO4, in a clean test tube. place with the evolution of a
Warm it and add a little of colourless, odourless gas.
the salt into it.
2.Warm the above reaction 2. First lime water turns milky

2. CO32-is confirmed.
mixture to get more gas and and with excess of the gas
pass the gas slowly through milkiness disappears.
limewater.
Explanation for Carbonate Test:
1. Na2CO3 + 2HCI → 2NaCl + H2O + CO2

Na2CO3 + H2SO4 → Na2SO4 + H2O + CO2
2. Milkyness is due to the formation of CaCO3, and with excess of the gas milkyness disappears
due to the formation of water soluble Ca(HCO3)2
Ca(OH)2 + CO2 → CaCO3↓ + H2O

White ppt.
CaCO3 + H2O + CO2 → Ca(HCO3)2

Soluble
Test for Sulphide (S2-):

1.Take 2 ml of dil. HCl or dil. 1. Effervescence takes place 1. It may be H2S from S2-
H2SO4, in a clean test tube. with the evolution of a colourless
Warm it and add a little of the gas with rotten egg smell.
salt into it.
2.Warm the above reaction 2. The filter paper turns black

2. S2-is confirmed.
mixture and show a filter paper
soaked with lead acetate to the
evolved gas.
Explanation for Sulphide Test:

1.
Na2S + 2HCI → 2NaCl + H2S
Na2S + H2SO4 → Na2SO4 + H2S
2. The black colour is due to the formation of PbS
(CH3COO)2Pb + H2S → 2CH3COOH + PbS↓

Black
Test for Chloride (Cl -):

1.Take a pinch of salt in a clean 1. Effervescence takes place 1. It may be HCl from Cl-
and dry test tube and add 2 to with the evolution of a colourless
3 drops of conc. H2SO4to it. gas which fumes in moist air.
2.Warm the above reaction 2. Dense white fumes are 2. It is due to the formation of
mixture and show a glass rod produced and white solid NH4Cl
dipped in conc. NH4OH to the deposited on the tip of the glass Cl-may be present.

mouth of test tube. rod.
3. Take a pinch of salt in a 3.Greenish yellow gas is called 3.Chlorine gas comes out from
clean and dry test tube add a which turns filter paper soaked in chloride which liberates iodine
little MnO2&2 to 3 drops of starch iodide solution blue. from iodide
conc. H2SO4to it and heat the
reaction mixture.
4.Take 1-2 ml of the supplied 4.A curdy white precipitate is 4. It is due to the formation of
salt solution. Acidify it with 1-2 formed AgCl
ml of dilute HNO3 and add few Cl-may be present.
drops of AgNO3 solution to it.
5.Wash the above of precipitate 5. Part I- The precipitate does 5. AgCl is not soluble in dil
with distilled water and divided not dissolve HNO3
into two parts. Part II- The precipitate does
Part I- Add dil HNO3and shake dissolve. AgCl is soluble in dil NH4OH due
well. to the formation of silver diamino
Part II- Add dil NH4OH and complex.
shake well. Cl-may be present.
Explanation for Chloride Test:
1. NaCl + H2SO4 → NaHSO4 + HCl ↑ (Colorless gas)
NaCl + NaHSO4 → Na2SO4 + HCl ↑
2. NH4OH + HCl → NH4Cl + H2O

White fumes
3. 2NaCl + MnO2+ 2H2SO4→ Na2SO4 + MnSO4 + Cl2 ↑+ 2H2O

Greenish yellow gas
2KI + Cl 2→ 2KCl + I2
4. NaCl + AgNO3 → NaNO3 + AgCl
White ppt.
5. AgCl + 2 NH4OH → [Ag(NH3)2] Cl + 2H2O
Diamino Silver (I) Chloride
(Water soluble complex)
-
Test for Nitrate (NO3 ):
1.Take a pinch of salt in a clean 1.Copious brown fumes are 1. Brown fume is due to NO2
and dry test tube. Add few evolved and the solution turns from NO3- salt.
pieces of copper turnings and 4 green or bluish green.
to 5 drops ofconc. H2SO4and
heat it.

2. Show a filter paper soaked in 2. The paper turns black. 2. May be NO3-
freshly prepared FeSO4
Solution to the above brown
gas.
3.Brown Ring Test:Take 1-2
ml. of the salt solution. Add 3.A brown ring is formed at the 3.The brown ring is due to the
equal volume ofconc. junction of the two liquid layers. formation of [Fe(NO)]SO4
H2SO4slowly into the test tube.
Cool the test tube perfectly NO3-is confirmed
under tap. Then slowly add 2-3
ml of freshly prepared FeSO4
Solution through the sides of
test tube.
Explanation for Nitrate Test:
1.
2.
3.
Test for Sulphate (SO42-):

2-
1.Take about 1-2 ml of salt 1. A white precipitate is 1. SO4 is confirmed.
solution. Acidify with 1-2 ml of obtained.
dil. HCl add about 1 ml of BaCl2
solution.
Add about 1 ml of conc. HCl to
the above solution and warm it.
The precipitate is not soluble.
Explanation for Sulphate Test:
The white precipitate is due to the formation of BaSO4 which is insoluble in conc. HCl.

1.What is acid radicals ?
2.How do u test for carbonate ?
3.What is the chemical equation involved in the test for sulphate ion ?
4.How do you test for sulphide ion ?
5.How can you test for nitrate ion ?
6.How does a salt become crystalline and amorphous?
7.How do you detect the presence of phosphate ion ?
8.Give the example of chemical reaction which involved for carbonate radicals ?
9.The acid radical carries ------- ion.
10.What is brown ring test ?

EXPERIMENT NO-6:

Test for ammonium, zinc, magnesium, aluminium, calcium, sodium & potassium (Known)
APPARATUS REQUIRED:
1. Test tube holder
2. Watch Glass
3. Blow pipe
4. Nichrome wire
5. Blue glass
6.Charcoal cavity
7.Test tubes
CHEMICALS REQUIRED:
1.Given salts
2.Various Reagent
3. Litmus paper
THEORY & PROCEDURE:

A.DRY TEST FOR BASIC RADICALS:
I. Heating in a dry Test Tube.
Heat a small quantity of a) Water particles condense at a) Salt contains water of
supplied salt in a clean, dry test the cooler part of the test-tube. crystallisation.
tube first slowly and then
strongly for about 3 to 4 b) A sublimate is formed. b) Volatile Salts
minutes.
White sublimate NH4NO3 is May be NH4+ , Hg2+ or As3+ salts
volatile but produces no white
sublimate.
c) The salt decrepitates.
(produces cracking sound) c) Crystalline Salts.
d) Deflagation takes place.
(Catches fire)
e) Infusible mass left. d) Some nitrate or nitrite salts.

f) The salt changes colour:
i) Yellow when hot and white e) May be Mg2+, Al3+, Zn2+ etc.
when cold.
ii) Red to black when hot and
brown when cold.
g) The salt is fused on heating f) (i) May be Zinc (Zn2+ ) salt
and solidified on cooling.
2+ 3+
h) The salt is swelled up on ii) May be Fe or Fe
heating.
g) May be alkali or alkaline earth
A gas or vapour is evolved. metal salts.
(i) A colourless, odourless gas

(CO2) which turns lime water
milky. h) May be Al3+
(ii) A colourless gas (NH3) with
pungent odour which turns red
litmus paper blue.
(i) May be carbonate salts.
(ii) May be ammonium salts.
. Heating in a Charcoal Cavity.

Make a small cavity on a (i) The salt decrepitates or
charcoal block. Fill the with the produces cracking sound.
supplied salt. Moisten the salt (ii) The salt volatilises completely (i) Crystalline salts.
with a drop of water. Heat the with white fumes.
salt strongly with the oxidising
flame for about three minutes
with help of a blow pipe. (iii) The salt deflagrates (ii) May be ammonium, arsenic
(iv) The salt may or may not melt or mercury salts
but finally leaves a white (Perform soda lime and bulb
infusible incandescent (giving
tube test).
light) residue.
(v) The salt melts and sinks into
the charcoal cavity on heating (iii) May be nitrate or nitrite
and reappears on cooling.
(iv) Aluminium, zinc, magnesium,

tin or alkaline earth metal salts.
(Perform cobalt nitrate test).
(vi)The salt is coloured and (v) May be alkali or alkaline on
leaves a coloured residue. earth metal salts (Perform flame
test).
(vi) May be chromium,

manganese, iron, cobalt, nickel
or copper salts. (Perform borax
bead test).
III. Soda lime Test: (For Volatile Salts)

Take a pinch of the salt in a a) A colourless gas with smell of
watch glass. Add a little ammonia is evolved which a) NH4+is present.
sodalime (NaOH + CaO) and produces a dense white fume
with concentrated HCl.
few drops of water to it. Rub it
with the thumb.
IV. Cobalt Nitrate Test: (For Infusible Salts)

Heat a small quantity of the a) Blue (infusible) mass. a) May be aluminium salt.
salt in charcoal cavity in the
oxidizing flame with the help of b) Green mass. b) May be Zinc Salt.
a blow pipetill an infusible and
incandescent residue is left. c) Pink mass c) May be Magnesium Salt.
Moisten in the Residue with a
d) May be Calcium Salt.
drop of Cobalt Nitrate solution d) Grey mass
and heat in the oxidising flame.
Note the colour of the residue

V. Flame Test: (For fusible Salts)

Clean a nichrome wire or a Colour of the flame
Platinum wire by robbing it with In naked eye Through Double
Sandpaper.Dip in concentrated blue glass
HCl taken in a watch i) Golden Yellow
ii) Violet i) Colourless
glass.Show it to the non- iii) Brick Red ii) Crimson red
luminous Bunsen flame till it iv) Yellowish iii) Light Green
imparts no colour to the Green iv) Bluish Green (i) May be Sodium salt.
Bunsen flame. Moisten the
clean where with concentrated ii) May be Potassium Salt.
HCl and touch it with a little of
the powdered salt. Show it to iii) May be Calcium Salt.
the non-luminous flame.
iv) May be Barium Salt.
Observe the colour of the flame
in naked eye and through
double blue glass.
VI. Charcoal Cavity Reduction Test: (For White salts changing Colour):

Prepare an intimate mixture of i) White shinning malleable bead a) May be lead salt.
salt charcoal powder and fusion with lemon yellow incrustation
mixture in 1: 3: 1 proportion. and the bead marks paper.b)
Take a little of this mixture in a Red Scale without incrustation.
charcoal cavity and heat it in b) May be Copper Salt.
reducing flame with the help of
a blow pipe.
 B.WET TEST FOR BASIC RADICALS:
Test For NH4+:

1. To about 1-2 ml of salt 1. Ammonia gas is evolved 1. NH4+ is confirmed.
solution is treated with dil. producing white fumes with a
NaOH and boiled. glass rod dipped in conc. HCl.
2. To 1-2 ml. of the salt 2. Brown ppt. is obtained. 2. NH4+ is confirmed.

solution, about 1ml dil. NaOH [ This is due to formation of
solution is added followed with I-Hg-O-Hg-NH2 ]
a little Nessler’s reagent.

Explanation for NH4+Test:
1.
2.
Brown ppt
2+
Test For Zn :

1. To about 1-2 ml of salt 1. A white precipitate is 1. May be Zn2+.
solution solid NH4Cl is added till obtained. [It is due to the formation of ZnS]
saturation and dil. NH4OH is
added till ammoniacal and H2S
is passed through it.
2. To about 1-2 ml. of the salt 2. Zn2+ is confirmed.
solution, dil. NaOH solution is 2. A white precipitate is first [The white ppt. is due to the
added drop by drop and then in obtained which is soluble in formation of Zn(OH)2 which gets
excess. excess of the reagent. dissolved with excess of the
reagent due to the formation of
3. To about 1-2 ml of salt Na2ZnO2.
solution few drops of 3. Zn2+ is confirmed.
K4[Fe(CN)6] solution is added. 3. A white precipitate is [This is due to the formation of
obtained. Zinc ferrocyanide]
Explanation for Zn2+Test:

1.
2.
3.
4.
Test for Mg2+

1. To about 1-2 ml of salt 1. A white precipitate is 1. May be Mg2+.
solution solid NH4Cl is added till obtained. [This is due to the formation of
saturation and dil. NH4OH is Mg(NH4)PO4].
added till alkaline and disodium
hydrogen phosphate solution is
added to it.
2. To about 1-2 ml. of the salt 2. Mg2+ is confirmed.

solution about 1 ml of dil. HCl is 2. A blue precipitate is obtained. [This is due to the formation of
added followed with 2-3 drops magnesium salt of magneson
of Magneson reagent and the reagent.]
solution is made strongly
alkaline with NaOH solution.

Explanation for NH4+Test:
3.
4.
Brown ppt
2+
Test For Zn :

1. To about 1-2 ml of salt 1. A white precipitate is 1. May be Zn2+.
solution solid NH4Cl is added till obtained. [It is due to the formation of ZnS]
saturation and dil. NH4OH is
added till ammoniacal and H2S
is passed through it.
2. To about 1-2 ml. of the salt 2. Zn2+ is confirmed.
solution, dil. NaOH solution is 2. A white precipitate is first [The white ppt. is due to the
added drop by drop and then in obtained which is soluble in formation of Zn(OH)2 which gets
excess. excess of the reagent. dissolved with excess of the
reagent due to the formation of
3. To about 1-2 ml of salt Na2ZnO2.
solution few drops of 3. Zn2+ is confirmed.
K4[Fe(CN)6] solution is added. 3. A white precipitate is [This is due to the formation of
obtained. Zinc ferrocyanide]
Explanation for Zn2+Test:

5.
6.
7.
8.
Test for Mg2+

1. To about 1-2 ml of salt 1. A white precipitate is 1. May be Mg2+.
solution solid NH4Cl is added till obtained. [This is due to the formation of
saturation and dil. NH4OH is Mg(NH4)PO4].
added till alkaline and disodium
hydrogen phosphate solution is
added to it.
2. To about 1-2 ml. of the salt 2. Mg2+ is confirmed.

solution about 1 ml of dil. HCl is 2. A blue precipitate is obtained. [This is due to the formation of
added followed with 2-3 drops magnesium salt of magneson
of Magneson reagent and the reagent.]
solution is made strongly
alkaline with NaOH solution.

Test For Na+:

+
1. To about 1-2 ml of salt 1. A White precipitate is 1. Na is confirmed.
solution about 1 ml of obtained. [The ppt. is due to the formation
potassium pyroantimonate of Na2H2Sb2O7]
solution is added and the inner
side of the test tube is
scratched with glass rod.
Explanation for Na+Test:

1.
White ppt. of Sodium Pyroantimonate
Test For K+:

+
1. To about 1-2 ml of salt 1. A Yellow precipitate is 1. K is confirmed.
solution solid NaNO2 is added obtained. [This is due to the formation of
till saturation followed with few K3[Co(NO2)6]].
drops Co(NO3)2 solution. About
1 ml of dil. CH3COOH is added
to it and the solution is kept for
sometime.
Explanation for K+Test:
1.
2.
3.
4.

1.What is dry test?
2.Which type of salt is subjected to sodalime test?
3.Which type of salt is subjected to flame test?
4.What type of wire can be used in the flame test?
5.What is wet test of salt
6.What are the group-I radicals and how they precipitated?
7.For what type of salts charcoal cavity reduction test is performed ?
8.For what type salt cobalt nitrate test is carried out?
9.What is the principle of charcoal cavity reduction test ?
10.Which dry test is applied for infusible salt to identify its basic radicals

EXPERIMENT NO-7

Test for unknown acid radicals.
APPARATUS REQUIRED:
1. Test tube holder
2. Bunsen Burner
3. Spatula
CHEMICALS REQUIRED:
1.Given salts
2.Various Reagent
3. Litmus paper
THEORY & PROCEDURE:

PRELIMINARY TEST:
1.Salt No----------
2.Colour of the salt----------
3.Structure----------
4.Solubility of the salt--------
B. TEST FOR ACID RADICALS:

2- 2-
I. Test with dil. HCl ( For CO3 , S )
About 2ml of dil. HCl is taken in a (a) Effervescence takes place (a) It may be CO2 from CO32-
clean test tube. It is warmed and with the evolution of a
small amount of the supplied salt colourless, odourless gas.
2-
is added to it. (b) Effervescence takes place (b) May be H2S from S .
with the evolution of a
colourless gas with the smell of
rotten egg.
(c) No effervescence and no (c) CO32-,S2- are absent.
gas is evolved.

Confirmatory Test for CO32-
The gas evolved from the reaction Lime water is turned milky and CO32- is confirmed.
of dilute HCl and the salt is with excess of gas
passed through lime water disappeared.
Confirmatory Test for S2-
The gas is passed through lead It is turned into black. S2- is confirmed.
acetate solution or a filter paper
dipped in lead acetate solution is
shown to the gas

-
II.(a) Test with conc. H2SO4 For Cl
A Pinch of salt is taken in a (a) Effervescence takes place (a) May be Cl-
clean and dry test tube. About with the evolution of a colourless
(Confirm by AgNO3 test.)
2 to 3 drops at conc. H2SO4 gas with pungent odour. White
was added. Then it was fumes were produced when a
warmed slightly glass rod dipped in conc. NH4OH
is shown to the gas. -
(d) No effervescence and no gas (d) Cl is absent.
is evolved.
-
(b)Confirmatory Test for Cl (Silver Nitrate Test)
About 1 ml of salt solution (i) Curdy white precipitate (i) Cl- is confirmed.
taken in a test tube is acidified soluble in dilute NH4OH which
with dilute HNO3 and AgNO3 reappeared on addition of
solution is added dil.HNO3.

III.(a) Test for NO3- (Conc. H2SO4 and Copper turning )
A little of the salt is heated with Brown fumes are evolved and (a) May be NO3-
concentrated H2SO4 and a few solution in test tube is turned
copper turnings. green.

(b) Brown Ring Test for NO3- (Confirmatory Test for NO3-)
To about 1 ml of salt solution A brown ring is formed at the NO3- is confirmed.
taken in a test tube equal junction of the two rings.
volume of concentrated H2SO4
is added. It is cooled under tap
water. Then freshly prepared
FeSO4 solution is added slowly.

IV. BaCl2Test for SO42- (Confirmatory Test for SO42-)
About 1 ml of salt solution White precipitate is obtained SO42-is confirmed.
taken in a test tube is acidified which is insoluble in
with dilute HCl and BaCl2 concentrated HCl even on
solution is added boiling
CONCLUSION:
Acid radical of the salt is detected to be-------------

EXPERIMENT NO-8

Test for unknown basic radicals.
APPARATUS REQUIRED:
1. Test tube holder
2. Watch Glass
3. Blow pipe
4. Nichrome wire
5. Blue glass
6.Charcoal cavity
CHEMICALS REQUIRED:
1.Given salts
2.Various Reagent
3. Litmus paper
THEORY & PROCEDURE:
PRELIMINARY TEST:
1.Salt No----------
2.Colour of the salt----------
3.Structure----------
4.Solubility of the salt------
A.DRY TEST FOR BASIC RADICALS:
I. Dry Test tube heating

In a clean and dry test tube. A (a) Water vapours condensed at (a) Salt with water crystallisation.
pinch of the salt is heated. the cooler part of the test tube.
(b) Decrepitation took place. (b) May be crystalline salt

III. Sodalime Test.( for Volatile Salt)
(c) Salt is volatilised and white (c) May be Volatile salt of NH4+ ,
sublimate is formed. As3+ and Hg2+.
(d) May be Mg2+, Al3+, Zn2+, Ba2+,
(d) Salt is first melted and finally
Ca2+, Sr2+ etc.
infusible white mass left.
(e) May be alkali or alkaline
(e) Salt is fused on heating and earth metal.
solidified on cooling.
(f) The colour of the salt is (f) May be salt of Pb2+, Bi2+ ,Sn2+
changed etc. The salt is non-volatile.
(i) Yellow when hot and white (i) May be Zn2+salt.
when cold.
(ii) Yellow when Hot and Cold
(iii) Yellowish brown in hot and (ii) May be Pb2+salt.
yellow when cold. (iii) May be Sn2+or Bi3+ salt.
(iv) Black residue.
(iv) May be Cu2+ ,Ni2+ ,Mn2+ or

Fe2+ salt.
II. Heating in a Charcoal Cavity.
A pinch of the salt is taken in a (a) Salt is completely volatilised. (a) May be salt of NH4+, As3+ and
charcoal cavity and is heated in Hg2+. (Sodalime test is to be
oxidising flame with a blow performed ).
pipe.
(b) May be Mg2+, Al3+, Zn2+, Ba2+,
(b) An infusible incandescent
Ca2+,Sr2+,Sn2+etc.(Cobalt nitrate
white mass is obtained.
test is to be performed ).
(c) The salt is fused and sank (c) May be alkali or alkaline
into the charcoal cavity and earth metal salt. (Flame test is to
reappeared on cooling. be performed).
(d) May be salt of Pb2+, Bi2+, Sn2+
(d) Original salt is white and Ag+ etc. (Reduction test is to be
formed a coloured mass. performed).
3+ + 2+
(e) Original salt is coloured and (e) May be Cr , Ag , Mn etc.
formed a coloured mass. (Borax bead test is to be
performed).

A pinch of salt is taken in a (a) Ammonia gas is evolved and (a) May be NH4+
watch glass. A little soda lime is the colour of the mixture is not
added with a drop of water. changed.
Then it is rubbed. (b) May be Hg2+.
(b) Only colour of the residue is
changed to brown and there is
no evolution of gas. (c) May be As3+
(c) No gas is evolved and no
change in colour of residue.
IV. Bulb tube test.( for Volatile Salt)
A mixture of salt, anhydrous (i) a white shinning mirror is (a) May be Hg2+.
Na2CO3 and charcoal powder in formed
the proportion of 1: 3: 1 was
(ii) A black shinning mirror is
prepared. A little of the mixture (b) May be As3+
formed with the evolution of a
is taken in a bulb tube and
gas having garlic colour.
heated.
V. Cobalt Nitrate test. (For infusible Salt)

A Pinch of salt is taken in a (i)Blue Mass (a) May be Al3+.
charcoal cavity. It is heated in
(ii)Green Mass (b) May be Zn2+
an oxidizing flame till an
infusible mass is obtained. A (iii)Pink Mass (c) May be Mg2+
drop of cobalt nitrate solution is (iv)Grey Mass (d) May be Ca2+
added and again heated
strongly. (Flame test to be performed.)
VI. Flame test. (For fusible Salt)

A clean nichrome wire is Colour through Colour through
moisten with concentrated HCl naked flame double blue
and touch it with a little of the glass.
powdered salt. Show it to the i) Golden i) Colourless (a) May be Na+.
non-luminous flame. Observe Yellow
the colour of the flame in naked
eye and through double blue ii) Violet ii) Red (b) May be K+
glass.
iii) Brick Red iii) Light Yellow
(c) May be Ca2+
VII. Charcoal Reduction Test. (For white salt changing colour)

A mixture of salt and fusion (i) White shining malleable bead (i) May be Ag+.
mixture in the proportion of 1:1 without incrustation which did
is prepared. A little of this not mark on paper.
mixture is taken in a charcoal
(ii) White shining malleable bead

cavity and is heated in a with lemon yellow incrustation (ii) May be Pb2
reducing flame. which marked on paper.
.WET TEST FOR BASIC RADICALS:
1. WET TESTS FOR BASIC RADICALS (Group Analysis)
Experiment Observation Inference

1. To 1ml. of salt solution in a clean a. A white precipitate is a. One of the Gr. I
test tube 1 cc. of dil HCI is added. formed. basic radicals (Pb2+,
Ag+, Hg22+) may be
present (Analysis of
Gr. I basic radicals
should be
performed)
b. No white precipitate is b. Gr. I basic radicals
formed are absent.
2. To 1ml. of the supplied salt solution a. A precipitate is a. One of the Gr III A
in a clean test tube solid NH"CI is obtained, (colour basic radicals (Fe3+,
added till saturation followed by should be noted) Al3+, Cr3+)may be
addition of dil NH4OH till alkaline. present (Analysis of
Gr III A basic
radicals should be
performed)
b. No precipitate is b. Gr III A basic
formed. radicals are absent.
3. Through the contents of the above a. Precipitate is formed a. One of the Gr III B
test tube H2S gas is passed under (colour should be basic radicals (Zn2+,
pressure. noted). Mn2+, Co2+, Ni2+)
may be
present(analysis of
Gr III B radicals
should be
performed)
b. No precipitate is b. Gr III B basic
formed radicals are absent.
4. To 1 cc of the salt solution is taken a. Precipitate is formed a. One of the Gr IV
in a clean test tube solid NH4Cl is (colour should be basic radicals (Ba2+,
added till saturation followed by noted). Sr2+, Ca2+) may be
addition of dil NH4OH till alkaline. present(analysis of
To this saturated solution of Gr IV radicals
ammonium carbonate is added. should be
performed)
b. No precipitate is b. Gr. IV basic radicals
formed. are absent.
The above basic radicals are absent indicating that one of the Gr. V basic radicals may be
present. As there is no specific group reagent for Gr. V test for individual radicals should be
performed

2. ANALYSIS OF BASIC RADICALS (GROUP WISE)
i) Analysis of Gr. IIIA Basic Radicals (Al3+)

1. 1 – 2 cc of the supplied A white ppt. is formed. May be Al3+
salt solution is saturated
with solid NH4Cl followed
by the addition of dil
NH4OH solution till
alkaline.
2. 1 – 2 cc of the supplied A white ppt. of Al(OH)3 is formed which May be Al3+
salt solution is treated with dissolved in excess of the reagent.
dil NaOH solution drop
wise and then in excess.
3. 1 cc of the supplied salt A gelatinous white ppt. of AlPO4 is formed Al 3+ confirmed.
solution, disodium which is soluble in dil. HCl solution.
hydrogen phosphate
solution is added.
ii) Analysis of Gr. IIIB Basic Radicals (Zn2+)

1. 1 – 2 cc of the supplied A white ppt. is formed. May be Zn2+
NH4OH solution till
alkaline. Then H2S gas is
passed through it.
2. 1 -2 cc of the supplied A white ppt is obtained. May be Zn2+
salt solution is treated
with potassium
ferrocyanide solution drop
by drop and then in
excess.
3. Dil. NaOH solution is A gelatinous white ppt. is formed which is Zn2+ confirmed.
added to 1 cc of the salt soluble in excess of NaOH solution.
solution drop by drop and
then in excess.
iii) Analysis of Gr. IV Basic Radicals (Ca2+)

1. 1 – 2 cc of the supplied A white ppt. of CaCO3 is formed. May be Ca2+
with solid NH4Cl and then
made alkaline with dil

NH4OH solution. Then
saturated solution of
ammonium carbonate
[(NH4)2CO3] is added.
2. The above ppt. is A white ppt. of CaC2O4 is formed which is May be Ca2+
dissolved in a minimum soluble in dil. HCl but insoluble in
quantity of dil CH3COOH. CH3COOH.
The solution is boiled to
remove CO2 and then
ammonium oxalate
solution is added to it.
ii) Analysis of Gr.V Basic Radicals (NH4+, Na+, K+)
Tests for NH4+

1. A small quantity of the salt is A colourless gas having smell of NH4+ confirmed.
treated with soda lime and ammonia which produced dense white
two drops of water and then fumes with a glass rod dipped in conc.
the mixture is rubbed in a NH4OH. There is no change in the
mortar. colour of the residue.
2. Nessler’s reagent is added to A brown ppt. is obtained. NH4+ confirmed.
1 cc of the salt solution.
Tests for Mg2+

1. 1 – 2 cc of the supplied A white ppt. is formed. May be Mg2+
NH4OH solution till
alkaline. Then dihydrogen
sodium phosphate
2. 1 cc of the salt solution is A blue ppt. is obtained. Mg2+ confirmed.
acidified with dil. HCl and
then treated with a few
drops of magneson
reagent followed by the
addition of excess of dil
NaOH solution.
Tests for Na+

+
1. Potassium A white crystalline ppt. is formed. Na confirmed.
pyroantimonate solution is
added to 1 cc of the
supplied salt solution.

Tests for K+

+
1. 1 cc of the salt solution is A yellow ppt. is formed. K confirmed.
treated with two drops of
cobalt nitrate solution
followed by the addition
of solid NaNO3 and dil.
CH3COOH solution.
Hence, the basic part of the supplied salt is _________.

EXPERIMENT NO. 09
(Tests for Unknown Salt)

Test for unknown basic radicals.
APPARATUS REQUIRED:
1. Test tube holder
2. Watch Glass
3. Blow pipe
4. Nichrome wire
5. Blue glass
6.Charcoal cavity
CHEMICALS REQUIRED:
1.Given salts
2.Various Reagent
3. Litmus paper
THEORY & PROCEDURE:
1. Preliminary Test:
(a) Salt No:

(b). Colour of the Salt : Colourless / name of the colour
(c) . Structure of Salt : Crystalline/ Amorphous
(d). Solubility:
i)Soluble in cold water (if not)
ii) Soluble in hot water (if not)
iii) Soluble in dilute HCl (if not)
iv) Soluble in hot dilute HCl
v) If not then salt is insoluble (*Salt soluble in dil HCl implies Gr.I basic radicals
absent)
2. DRY TEST FOR BASIC RADICALS
Dry Test Tube heating:

A small quantity of salt is (a) A sublimate is formed (a) It is volatile salt, (Soda lime
taken in a clean and dry test (Note the colour of the test and bulb tube test should
tube and heated strongly in sublimate) be performed.)
the hottest part of the non- b )Water particles condense (b) Salt contains water of
luminous flame. at the cooler part of the test crystallisation.
(c) Decripitation or cracking (c) May be crystalline salt.
sound is produced.
(d) Deflagration takes place. (d) The salt may be nitrate of
alkali or alkaline earth
metal.
(e) The salt changes colour. (e) It may be Zinc salt.
Yellow when hot and white
when cold.

(f) Salt fuses on heating and (f) May be alkali or alkaline
solidifies on cooling. earth metal salt.
3. SODALIME TEST:

A little of the salt is taken in a A colourless gas evolved with strong NH4+ may be
clean watch glass along with smell of ammonia and colour of the present. (To be
soda-lime and it is rubbed by mixture is unchanged. confirmed in the
adding two drops of water. wet test)
4. CHARCOAL CAVITY HEATING (OXIDISING FLAME)

A little of the Salt is taken in a. The salt decrepitates. a. Maybe crystalline salt.
the charcoal cavity and b. The salt deflagrates. b. May be NO3- salt
heated by oxidizing flame with c. The salt fuses and sinks into c. Salt contains alkali or
the help of a blow pipe. the charcoal cavity. alkaline earth metal.
(Flame test should be
performed).
d. Infusible incandescent white d. Cobalt nitrate test
residue. should be performed.
5. COBALT NITRATE TEST

The salt is taken in the a. Blue mass is obtained. a. Al3+ may be present.
charcoal cavity and heated in b. Green mass is obtained. b. Zn2+ may be present.
the oxidizing flame with the c. Rosy mass is obtained. c. Mg2+ may be present.
help of a blow pipe till an d. Grey mass is obtained. d. Ca2+ may be present.
infusible, incandescent white
mass is obtained. Then one
drop of cobalt nitrate solution
is added to it and heated
strongly.
6.FLAME TEST

The nichrome wire is cleaned a. Persistent golden Yellow a. Na+ may be present.
with sand paper and dipped in coloured flame is seen in
conc. HCI and shown to non- naked eye and colourless
luminous flame. This process through double blue glass. b)
is repeated till no colour is Violet flame is seen in naked
imparted to the flame. Then eye and red through a pair of
the wire is moistened with blue glass.
conc. HCI and a little of the b. Violet flame is seen in naked b. K+ may be present.
salt is taken by touching to the eye and red through a pair of
salt is taken by touching to the blue glass.
salt and shown to the c. Brick red flame is observed. c. Ca2+may be present.
oxidizing flame.

7.IDENTIFICATION OF ACID RADICAL
Test for Gr- I acid radicals (Carbonate and Sulphide)

1 cc dilute HCl taken in d test 1. Effervescence took place a. Carbonate (CO32 – ) may
tube and slightly warmed. To with the evolution of a be present (other test
this a pinch of the supplied colourless odourless gas is should be performed for
salt is added. evolved. its confirmation.)
2. Effervescence took place a. Sulphide (S2 –) may be
with the evolution of a present (other test
colourless odourless gas should be performed for
with rotten egg smell is its confirmation.)
evolved.
Test for Gr- II acid radicals (Chloride)

–
A few drops of conc. H2SO4 is A colourless fuming gas with pungent Cl may be present.
taken in a clean and dry test odour is evolved. (Other test should
tube, a pinch of the supplied be performed for
salt is added in to it and is its confirmation).
gently warmed.
Test for Gr- III acid radicals (Nitrate and Sulphate)
TESTS FOR NITRATE (NO3 –)

A pinch of the supplied salt is A brown fume with pungent smell is May be NO3 –.
moistened with a few drops of observed. (Other test should
conc. H2SO4 is taken in a be performed for
clean and dry test tube and is its confirmation).
gently warmed.
TESTS FOR SULPHATE (SO42–)

1-2 cc of the salt solution is A white ppt. is obtained which is insoluble SO42 – confirmed.
taken in a clean test tube and in conc. HCl even on boiling.
is acidified with dil HCl. A few
cc of Barium chloride (BaCl2)
solution is added into it.

CONFIRMATORY TESTS FOR CARBONATE (CO32 –)

1. A burning match stick is shown to The burning stick extinguished. CO32– may be
the evolved gas. present.
2. A little more salt is added to the At first white turbidity (milk CO32–may be
above test tube and the colour) appeared which present
evolved gas is passed through disappeared with excess
lime water with the help of a passing of the gas.
delivery tube.
3. A little more salt is added to the No change of the colour took CO32– confirmed
above test tube and the evolved place.
gas is passed through acidified
potassium dichromate solution
with the help of a delivery tube.
CONFIRMATORY TESTS FOR SULPHISE (S2 –)

A filter paper soaked with Lead 1. The filter paper turned black. S2– Confirmed.
acetate solution is shown to the
mouth of the test tube.
CONFIRMATORY TESTS FOR CHLORIDE (Cl –)

–
1. A glass rod dipped in conc. A white dense fume is formed. Cl may be present.
NH4OH solution is shown to the
gas evolved.
2. A pinch of MnO2 is added to the A greenish yellow gas is formed Cl– may be present.
above test tube and is warmed which turned starch iodide paper
gently. blue.
3. A pinch of the given salt is taken A curdy white ppt. is formed Cl– confirmed.
in a clean and dry test tube and is which is soluble in dil NH4OH and
acidified with dil HNO3 solution. is insoluble in dil HNO3.
And a few drops of silver nitrate
(AgNO3) solution is added into it.
CONFIRMATORY TEST FOR NITRATE (NO3–)

1. A pinch of the supplied salt and Deep brown vapours are formed May be NO3 –.
a few copper turnings are taken and the solution turned bluish
in a clean test tube. 1 – 2 cc of green or green.
50% conc. H2SO4 is added into
it and is heated gently.
2. A piece of filter paper soaked in It turned black. May be NO3 –.
FeSO4 solution is shown to the

evolved gas.
3. 1 cc of the supplied salt solution A brown ring is formed at the NO3 –confirmed.
in water is taken in a clean test junction of the two liquids. The ring
tube. Equal volume of conc. disappeared on shaking.
H2SO4 is added in to the test
tube. The test tube is cooled
under tap water. And equal
volume of freshly prepared
ferrous sulphate (FeSO4)
solution is added from the side
of the test tube.
8.WET TESTS FOR BASIC RADICALS (Group Analysis)

1. To 1ml. of salt solution in a a. A white precipitate is a. One of the Gr. I
clean test tube 1 cc. of dil HCI formed. basic radicals (Pb2+,
is added. Ag+, Hg22+) may be
present (Analysis of
Gr. I basic radicals
should be
performed)
b. No white precipitate is b. Gr. I basic radicals
formed are absent.
2. To 1ml. of the supplied salt a. A precipitate is obtained, a. One of the Gr III A
solution in a clean test tube (colour should be noted) basic radicals (Fe3+,
solid NH"CI is added till Al3+, Cr3+)may be
saturation followed by addition present (Analysis of
of dil NH4OH till alkaline. Gr III A basic
radicals should be
performed)
b. No precipitate is formed. b. Gr III A basic
radicals are absent.
3. Through the contents of the a. Precipitate is formed a. One of the Gr III B
above test tube H2S gas is (colour should be noted). basic radicals (Zn2+,
passed under pressure. Mn2+, Co2+, Ni2+)
may be
present(analysis of
Gr III B radicals
should be
performed)
b. No precipitate is formed b. Gr III B basic
radicals are absent.
4. To 1 cc of the salt solution is a. Precipitate is formed a. One of the Gr IV
taken in a clean test tube solid (colour should be noted). basic radicals (Ba2+,
NH4Cl is added till saturation Sr2+, Ca2+) may be

followed by addition of dil present(analysis of
NH4OH till alkaline. To this Gr IV radicals
saturated solution of should be
ammonium carbonate is added. performed)
b. No precipitate is formed. b. Gr. IV basic radicals
are absent.
The above basic radicals are absent indicating that one of the Gr. V basic radicals may be
present. As there is no specific group reagent for Gr. V test for individual radicals should be
performed.
9.ANALYSIS OF BASIC RADICALS (GROUP WISE)
ii) Analysis of Gr. IIIA Basic Radicals (Al3+)

1. 1 – 2 cc of the supplied A white ppt. is formed. May be Al3+
NH4OH solution till
alkaline.
2. 1 – 2 cc of the supplied A white ppt. of Al(OH)3 is formed which May be Al3+
salt solution is treated with dissolved in excess of the reagent.
dil NaOH solution drop
wise and then in excess.
3. 1 cc of the supplied salt A gelatinous white ppt. of AlPO4 is formed Al 3+ confirmed.
solution, disodium which is soluble in dil. HCl solution.
hydrogen phosphate
solution is added.
iv.Analysis of Gr. IIIB Basic Radicals (Zn2+)

1. 1 – 2 cc of the supplied A white ppt. is formed. May be Zn2+
NH4OH solution till
alkaline. Then H2S gas is
passed through it.
2. 1 -2 cc of the supplied A white ppt is obtained. May be Zn2+
salt solution is treated
with potassium
ferrocyanide solution drop
by drop and then in
excess.
3. Dil. NaOH solution is A gelatinous white ppt. is formed which is Zn2+ confirmed.
added to 1 cc of the salt soluble in excess of NaOH solution.
solution drop by drop and

then in excess.
iv) Analysis of Gr. IV Basic Radicals (Ca2+)

1. 1 – 2 cc of the supplied A white ppt. of CaCO3 is formed. May be Ca2+
with solid NH4Cl and then
made alkaline with dil
NH4OH solution. Then
saturated solution of
ammonium carbonate
[(NH4)2CO3] is added.
2. The above ppt. is A white ppt. of CaC2O4 is formed which is May be Ca2+
dissolved in a minimum soluble in dil. HCl but insoluble in
quantity of dil CH3COOH. CH3COOH.
The solution is boiled to
remove CO2 and then
ammonium oxalate
3. Flame test is performed Brick red flame is noticed. Ca2+ confirmed.
with the white ppt. formed
above.
iii) Analysis of Gr.V Basic Radicals (NH4+, Na+, K+)
Tests for NH4+

1. A small quantity of the A colourless gas having smell of ammonia NH4+ confirmed.
salt is treated with soda which produced dense white fumes with a
lime and two drops of glass rod dipped in conc. NH4OH. There
water and then the is no change in the colour of the residue.
mixture is rubbed in a
mortar.
2. Nessler’s reagent is A brown ppt. is obtained. NH4+ confirmed.
added to 1 cc of the salt
solution.
Tests for Mg2+

1. 1 – 2 cc of the supplied A white ppt. is formed. May be Mg2+
NH4OH solution till
alkaline. Then dihydrogen
sodium phosphate
2. 1 cc of the salt solution is A blue ppt. is obtained. Mg2+ confirmed.

acidified with dil. HCl and
then treated with a few
drops of magneson
reagent followed by the
addition of excess of dil
NaOH solution.
Tests for Na+

1. Potassium A white crystalline ppt. is formed. Na+ confirmed.
pyroantimonate solution is
added to 1 cc of the
supplied salt solution.
Tests for K+

1. 1 cc of the salt solution is A yellow ppt. is formed. K+ confirmed.
treated with two drops of
cobalt nitrate solution
followed by the addition
of solid NaNO3 and dil.
CH3COOH solution.
Hence, the basic part of the supplied salt is _________ and the acid part of the salt is _______.
Thus, the salt supplied is ____________.


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Engineering Chemistry Practical

State Council for Technical Education and

SCTE&VT LR Material in Engineering Chemistry Lab 1

Engineering Chemistry Practical

Sri. Papun Mirddha, Lecturer in Chemistry, GP,Boudh.

Reviewed and validated by

Sri. Prabodh Kumar Satapathy, Lecturer in Chemistry,

SCTE&VT LR Material in Engineering Chemistry Lab 2

2 Preparation and Study of Properties of Amonia Gas

8 TEST FOR UNKNOWN BASIC RADICALS.

9 TEST FOR UNKNOWN SALT (COMPOSED OF ONE BASIC AND

SCTE&VT LR Material in Engineering Chemistry Lab 3

SCTE&VT LR Material in Engineering Chemistry Lab 4

AIM OF THE EXPERIMENT:

Fig 1.1 Laboratory Preparation of carbon dioxide gas.

SCTE&VT LR Material in Engineering Chemistry Lab 5

3. Nowpoursomewaterintothewoulf’sbottlethroughthethistlefunnelsoastocover the marble chips.

SL. EXPERIMENT OBSERVATION INFERENCE

1. Observe the colour ofthe gas

2. Observe the odour of the gas

into a test tube full of CO2gas.

4. Invert the test tube full of CO2 gas

SCTE&VT LR Material in Engineering Chemistry Lab 6

SL EXPERIMENT OBSERVATION INFERENCE

1 A piece of moist blue

2. Pass the CO2 gas through 2-3 ml of

SAFTY AND PRECAUTION:

2. The end of thistle funnel must be remaining deep inside thesolution.

the woulf’s bottle.

5. Addition of excess of dil. hydrochloric acid should beavoided.

6. The gas should be collected after removing air from theapparatus.

SCTE&VT LR Material in Engineering Chemistry Lab 7

SCTE&VT LR Material in Engineering Chemistry Lab 8

Preparation and study of properties of NH3 gas.

2. Anhydrous Calcium Hydroxide, Ca(OH)2 or Calcium Oxide (CaO)

Fig 2.1 Laboratory preparation of Ammonia Gas.

SCTE&VT LR Material in Engineering Chemistry Lab 9

3. Tilt the test tube at 30 degree angle and clamp it to thestand.

6.Now carefully and gently heat the mixture in the testtube.

SL. EXPERIMENT OBSERVATION INFERENCE

1 Color of the gas

2 Odour of the gas

3 Collect the gas in a test tube half-

SL. EXPERIMENT OBSERVATION INFERENCE

1 Show a piece of moist red litmus

SCTE&VT LR Material in Engineering Chemistry Lab 10

3 Pass the gas into the test tube

4 Pass the ammonia gas into the test

3. Heat should be provideduniformly.

4. The gas jar should bedried.

SCTE&VT LR Material in Engineering Chemistry Lab 11

SCTE&VT LR Material in Engineering Chemistry Lab 12

AIM OF THE EXPERIMENT:

Fig 3.1 Filtration

SCTE&VT LR Material in Engineering Chemistry Lab 13

(A) Preparation of Saturated solution :-

(B ) Concentrating the Filtrate :-

 Evaporate the filtrate in the porcelain basin with constant stirring.