FIRST YEAR PUCFIRST YEAR PUC

PRACTICALS SYLLABUSPRACTICALS SYLLABUS

Basic Laboratory TechniquesBasic Laboratory Techniques

1. cutting glass tube and glass rod1. cutting glass tube and glass rod1. cutting glass tube and glass rod1. cutting glass tube and glass rod

2. Bending a glass tube2. Bending a glass tube

3. Drawing out a glass jet3. Drawing out a glass jet

4. Boring a cork4. Boring a cork

Characterization and purification Characterization and purification of chemical substancesof chemical substances

1. Determination of melting point of an 1. Determination of melting point of an organic compoundorganic compound

1. Determination of melting point of an 1. Determination of melting point of an organic compoundorganic compound

2. Determination of boiling point of an 2. Determination of boiling point of an organic compoundorganic compound

3. crystallization of impure sample of 3. crystallization of impure sample of anyone of the following:anyone of the following:Alum, Copper Alum, Copper sulphatesulphate, Benzoic acid, Benzoic acid..

Experiments related to pH changeExperiments related to pH change

•• Any one of the following experiments:Any one of the following experiments:* Determination of pH of some solution * Determination of pH of some solution obtained from Fruit juice, varied concentration obtained from Fruit juice, varied concentration obtained from Fruit juice, varied concentration obtained from Fruit juice, varied concentration of acid, base and salts using pH paper or of acid, base and salts using pH paper or universal indicator.universal indicator.* Comparing the pH of solution of strong and * Comparing the pH of solution of strong and weak acid of same concentrationweak acid of same concentration* Study the pH change in the titration of a * Study the pH change in the titration of a strong base using universal indicator.strong base using universal indicator.

•• Study the pH change by common ion effect in Study the pH change by common ion effect in case of weak case of weak acid and weak acid and weak base.base.

Chemical equilibriumChemical equilibrium

•• Study the shift in equilibrium Study the shift in equilibrium between ferric ions and between ferric ions and thiocyanatethiocyanateion by increasing/ decreasing the ion by increasing/ decreasing the ion by increasing/ decreasing the ion by increasing/ decreasing the concentration of either ions.concentration of either ions.

•• Study the shift in equilibrium Study the shift in equilibrium between [Co(Hbetween [Co(H22O)O)66]]2+2+ and chloride and chloride ions by changing the concentration ions by changing the concentration of either of the ions.of either of the ions.

Quantitative estimation:Quantitative estimation:

•• Using a chemical balance.Using a chemical balance.•• Preparation of standard solution of oxalic Preparation of standard solution of oxalic acid.acid.acid.acid.

•• Determination of strength of a given Determination of strength of a given solution of NaOH by solution of NaOH by titrating it against titrating it against standard solution of oxalic acid.standard solution of oxalic acid.

•• Preparation of standard solution of sodium Preparation of standard solution of sodium carbonate.carbonate.

•• Determination of strength of a given Determination of strength of a given solution of HCl by titrating it against solution of HCl by titrating it against standard Nastandard Na22COCO3 3 solution. solution.

Qualitative analysis of inorganic saltQualitative analysis of inorganic salt

Determination of anion and cat ion in a Determination of anion and cat ion in a given salt.given salt.

Anions:Anions:--

COCO 33--, S, S--22, SO, SO 33--,, SOSO 44--, NO, NO --, , ClCl--, Br, Br--, , COCO3333--, S, S--22, SO, SO33

33--,, SOSO4444--, NO, NO33

--, , ClCl--, Br, Br--, ,

II--, PO, PO4433--, C, C22OO44

22--, CH, CH33COOCOO--..

Cat ions:Cat ions:--

PbPb2+2+, Cu, Cu2+2+, As, As3+3+, Al, Al3+3+, Fe, Fe3+3+, Mn, Mn2+2+, Ni, Ni2+2+, ,

ZnZn2+2+, Ca, Ca2+2+, Sr, Sr2+2+, Ba, Ba2+2+. .

•• Detection of nitrogen, Detection of nitrogen, sulphursulphur, chlorine., chlorine.

Common apparatus use Common apparatus use in Laboratory in Laboratory

and their usesand their uses

Conical flask

BuretteBuretteBuretteBurette

Measuring cylinder/ volumetric flask

Burette

Lower meniscus of solution in burette

Beaker

Test tubes and test stand

Separating funnel

Bunsen burner

Bunsen Flame

Round bottom flask

Tripod stand

Crucible tongs

Graduated/ measuring cylinders

Droppers

Test tube holders

Measuring cylinders

Watch Glass

Volumetric Measuring flask

Funnel

Reagent bottles

Wash bottle ( water bottle)

Wire gauze

Chemical Balance

Thiele’s Tube

Spatulla

Kipp’s apparatus

TEST TUBE BRUSH

Preparation of Preparation of Standard Solution of Sodium Carbonate

QUALITATIV ANALYSIS OF QUALITATIV ANALYSIS OF INORGANIC SALTINORGANIC SALT

Preliminary Examination of Salt.Preliminary Examination of Salt.

ColourColour

SoluilitySoluility

ANALYSIS OF ACIDIC RADICALS

Preliminary test with dilute Sulphuric Acid

Test Observation Inference

0.1g of Salt +dil

1)A colourless , Odourless gas Carbonate

Salt +dil H2SO4

warm

Odourless gas of CO2 is evolved with brisk effervescence, which turns lime water milky

Carbonate (CO3

2-) is present

2)Colourless gas of H2S with smell of rotten egg is evolved which turns lead acetate paper black

Sulphide (S2-) is present

black

3)Colourless gas SO2 with a pungent smell which turns acidified K 2Cr2O7

Solution green

Sulphite (SO3

2-) is present

4)Brown gas which turns acidified KI solution containing starch solution blue

Nitrite (NO2

-) is present

5)Colourless vapour with smell of

Acetate with smell of vinegar, vapour turns blue litmus red

Acetate (CH3COO

-) is present

Confirmatory test for COConfirmatory test for CO3322-- SS22-- SOSO33

22-- NONO33--

and CHand CH33COOCOO--

A) Carbonate ion (CO3

2-)

0.1g of salt + dilute H4SO4

CO2 gas evolved with bricsk effervescence which turn s lime water milky.milky.

D) Nitrite ion. (NO3

-)1 mL of water extract + few drop of KI solution and add few drop of starch solution acidify with acetic acid. Blue colour appears.

B) Sulphideion (S2-)

1mL of water extract + ammonium hydroxide add a drop of sodium nitroprusside solution. Purple or violet colouration appears.

C) Sulphiteion (SO3

2-)1 mL of ate extract + BaCl2 solution. A white ppt is formed which dissolves in dil. HCl.

E) Acetate ion (CH3COO

-)

0.1g of salt in a china dish add 1mL of ethanol and 0.2mL conc. Sulphuric acid and heat, Fruity odourevolved.

If no positive result obtained in step I then go for Step II

Step II: Preliminary test with conc Sulphuric acid:

Test

0.1 g of salt + 3-4 drop of Conc. Sulphuric

Observation Inference

1) Colourless gas with pungent which gives dense white fumes when a rod dipped in NH4OH is brought near

Chlorid ion (Cl-) is present

Sulphuricacid and Warm

NH4OH is brought near mouth of the test tube.

2) Reddish brown gas with pungent smell heating. After adding of solid MnO2, solution acquires red colour

Bromide ion(Br-) isPresent

3) Violet vapour which turns starch Paper blue and a layer of violet sublimate is formed on side of test tubefumes become dense on adding MnO2.

Iodide ion(I-) is Present

4) Brown fumes evolved which become dense by heating with cu- turning and solution turn blue colour.

Nitrite ion (NO3

-) is Present

5) Colourless gas, odourless gas evolved which turns lime water milky an gas coming out of lime water burns with

Oxalate ion (C2O4

2-) is Present

water burns with a blue flame if ignite.

Confirmatory test for Cl-,Br-, I-, NO3-, and

c2O42-. Radicals

A) Chloride ion.(Cl-)

a) 0.1g of salt + pich of MnO2

and 3-4 drop conc. H2SO4 heat the mixture Greenish yellow chlorine gas is evolved which gives pungent evolved which gives pungent odour.b) 1mL of sodium carbonate extract acidify with dil. HNO3 or take water extract and add silver nitrate solution . A curdywhite ppt. is obtained which soluble in NH4OH solution

B) Bromide ion. (Br-)

a) 0.1 g of salt + pinch of MnO2 add 3-4 drop conc. H2SO4 heat the mixture . Intense brown fumes evolved.b) 1mL of sodium extract acidified with dil. HNO or acidified with dil. HNO3 or take water extract and add silver nitrate solution. A pale yellow ppt which is slowly soluble in NH4OH solution.

C) Iodide Ion. (I-)

a) 1 mL of salt solution neutrilization with Hcl & add 1 mL CHCl3 or CCl4, now add an excess of chlorine water drop by drop and shake TT. A violet colour appears in the organic layer.organic layer.b) 1 mL of sodium carbonate extract acidify with dil HNO3

or takes water extract, add AgNo3 solution A yellow pptin soluble in NH4OH solution is obtained.

D) Nitrate Ion (NO3

-)1 mL Water extract add 2 mLconc. H2SO4 mix through cool the mixture under the tap. Add freshly prepared FeSO4

solution along the side of TT without shaking A dark brown ring is formed at the brown ring is formed at the junction of the two solution.

E) Oxalate ion (C2O4

2-

)

1 mL of water extract acidified with acetic acid and add calcium chloride solution. A white pptinsoluble in ammonium insoluble in ammonium oxalate and oxalic acid but soluble in dil Hcl & dilHNO3.

if no positive test is obtained in step I & II then go for step III

III Test for SOIII Test for SO4422-- and POand PO44

33--

••

Sulphate(SO4

-2)1 mL water extract + dilHCl +Bacl2 solution white

Confirmatory test for Sulphate & Phosphate ion

(SO4-2) HCl +Bacl2 solution white

ppt insoluble in conc. HCl is obtained.

Phosphate Ion (PO4

-3)1 mL water extract + conc. HNO3 and add ammonium molubidate solution & boil A canary yellow ppt is formed.

SYSTEMATIC QUALITATIVE SYSTEMATIC QUALITATIVE ANALYSIS OF INORGANIC SALTANALYSIS OF INORGANIC SALT

Preliminary examination of Preliminary examination of the salt the salt for for cationcation

Test Test Observation Observation InferenceInference

ColourColour

Light Light green, yellow, browngreen, yellow, brown FeFe22++,Fe,Fe33++

BlueBlue CuCu2+2+

Bright Bright greengreen NiNi22++

Blue, red, Violet, pinkBlue, red, Violet, pink CoCo22++

Light Light pinkpink MnMn22++

•• Dry heating test: Dry heating test:

0.1g 0.1g of salt is heated in dry test tube and observe of salt is heated in dry test tube and observe the the colourcolour of salt in hot and also when it become of salt in hot and also when it become cold.cold.cold.cold.ColourColour when coldwhen cold ColourColour when hotwhen hot InferenceInference

BlueBlue WhiteWhiteCuCu22++

GreenGreen Dirty white or yellowDirty white or yellow FeFe2+2+

White White yellowyellow ZnZn2+2+

PinkPink BlueBlue CoCo2+2+

•• Flame test:Flame test:Platinum Platinum loop is dip in the paste of salt and held in the loop is dip in the paste of salt and held in the nonnon--luminous flame. Observe the luminous flame. Observe the colourcolour of flame first of flame first with nicked eye and then through a blue glass.with nicked eye and then through a blue glass.

•• Color of flame Color of flame observed observed byby ColourColour of flame observed of flame observed bybyInferenceInference

•• Color of flame Color of flame observed observed byby ColourColour of flame observed of flame observed bybyInferenceInference

Naked Naked eyeeye through through blue glassblue glass

•• Green flame with blue Green flame with blue centercenter no no changechange CuCu22++

•• Crimson redCrimson red PurplePurple SrSr2+2+

•• Apple greenApple green Bluish Bluish greengreen BaBa22++

•• Brick Brick redred GreenGreen CaCa2+2+

Preparation of Original Preparation of Original solution(O.S.)solution(O.S.)

Salt Salt is dissolved in distilled water if not is dissolved in distilled water if not soluble then heat, if soluble then heat, if even insoluble even insoluble then then soluble then heat, if soluble then heat, if even insoluble even insoluble then then salt dissolved in dil. salt dissolved in dil. HClHCl or Conc. or Conc. HClHCl or or dil. HNOdil. HNO33 or a mixture of conc. or a mixture of conc. HClHCl and and COnc.COnc. HNOHNO33 in the ratio of 3:1 this in the ratio of 3:1 this mixture is called Aqua mixture is called Aqua regiaregia. A salt not . A salt not soluble in aqua soluble in aqua regiaregia is considered to be is considered to be an insoluble salt.an insoluble salt.

Analysis of Zero group cat ion (NHAnalysis of Zero group cat ion (NH44++

ion)ion)

•• 0.1 g of a salt and add 10.1 g of a salt and add 1--2mL of 2mL of NaOHNaOH solution and heat solution and heat If there is a smell of ammonia this indicate the presence If there is a smell of ammonia this indicate the presence of ammonium ions. Ring the glass rod dipped in of ammonium ions. Ring the glass rod dipped in HClHCl near near of ammonium ions. Ring the glass rod dipped in of ammonium ions. Ring the glass rod dipped in HClHCl near near the mouth of the test tube. White fumes are observedthe mouth of the test tube. White fumes are observed..

•• Pass the gas through Pass the gas through Nessler’sNessler’s reagent. Brown ppt. is reagent. Brown ppt. is obtainedobtained

ANALYSIS OF BASIC RADICALSANALYSIS OF BASIC RADICALS

Test Test observation Inferenceobservation Inference•• O.S. + dil. O.S. + dil. HClHCl White White pptppt II--group group PbPb2+2+ is presentis present

No No pptppt IIII--group group is is absentabsent

•• O.S. + dil. O.S. + dil. HClHCl + pass H+ pass H22S gas.S gas. Black Black PPt.PPt. IIII--group group CuCu2+2+, Pb, Pb2+2+•• O.S. + dil. O.S. + dil. HClHCl + pass H+ pass H22S gas.S gas. Black Black PPt.PPt. IIII--group group CuCu2+2+, Pb, Pb2+2+

YellowpptYellowppt AsAs33++ is presentis presentNo No ppt.ppt. IIII--group group is is absentabsent

•• O.S. + Solid NHO.S. + Solid NH44Cl Cl Brown ppt.Brown ppt. IIIIII--group group FeFe3+3+

+ excess NH+ excess NH44OH OH White White gelatinous gelatinous ppt. Alppt. Al33++ is presentis presentNo No ppt.ppt. IIIIII--group is absentgroup is absent

Test Test observationobservation InferenceInference

•• O.SO.S. +solid NH. +solid NH44Cl Cl White White PPtPPt.. IVIV--group Zngroup Zn2+2+

+ excessNH+ excessNH44OH OH Flesh Flesh colourcolour pptppt MnMn22++

+passH+passH22S. S. Black ppt.Black ppt. NiNi2+2+, Co, Co2+2+is is presntpresnt

No No ppt.ppt. IIVV-- group group is is absentabsentNo No ppt.ppt. IIVV-- group group is is absentabsent

•• o.so.s. + solid NH. + solid NH44Cl Cl White ppt.White ppt. VV--group group BaBa2+2+,Ca,Ca2+2+,Sr,Sr2+2+

+ excess NH+ excess NH44OH OH is present is present + solid (NH+ solid (NH44))22COCO33

No ppt.No ppt. VIVI-- group Mggroup Mg2+2+ is is presentpresent

Analysis of Group I Analysis of Group I cationcation: : ((PbPb2+2+))

•• Dissolve the Dissolve the pptppt in hot water and divide in hot water and divide into two parts.into two parts.into two parts.into two parts.

Part 1 + KI solutionPart 1 + KI solution yellow yellow pptppt PbPb2+2+ is confirmedis confirmed

Part 2 + potassium chromate Part 2 + potassium chromate Yellow Yellow pptppt which is Pbwhich is Pb2+2+ is is confirmedconfirmed

solutionsolution soluble In soluble In NaOHNaOH solutionsolution

Analysis of Group II Analysis of Group II cationcation:: (Pb(Pb2+2+, Cu, Cu2+2+ , , AsAs3+3+ ))

•• II group II group PPtPPt + yellow ammonium + yellow ammonium PPtPPt is insolubleis insoluble PbPb2+2+, Cu, Cu2+2+ is presentis presentSulphideSulphide solution and shakesolution and shake PPtPPt is solubleis soluble AsAs3+3+ is presentis present

•• Confirmatory test for PbConfirmatory test for Pb2+2+ and Cuand Cu2+2+ ionsions

•• II group II group pptppt boil with boil with White ppt.White ppt. PbPb2+2+ is confirmed is confirmed •• II group II group pptppt boil with boil with White ppt.White ppt. PbPb2+2+ is confirmed is confirmed dildil HNOHNO33and add few drop of and add few drop of alcohol and dil. Halcohol and dil. H2-2-SOSO44 ..

•• This White This White pptppt is dissolved in is dissolved in ammoniumAcetateammoniumAcetate + acetic acid+ KI + acetic acid+ KI yellow yellow pptppt PbPb2+2+is confirmedis confirmedSolutionSolution

•• If no white If no white pptppt add excess ofadd excess of Chocolate brown Chocolate brown pptppt CuCu2+2+ is confirmed is confirmed NHNH44OH solution + acetic acidOH solution + acetic acid+ potassium + potassium ferroferro cyanide solution.cyanide solution.

Analysis of Group III Analysis of Group III cationscations: : (Fe(Fe3+3+, Al, Al3+3+))

•• Brown Brown pptppt dissolve in dissolve in dildil HClHCl and divide the solution into two part.and divide the solution into two part.

•• Part I + potassium Part I + potassium Blue ppt. or Blue ppt. or FeFe3+3+ is confirmedis confirmed

ferrocyanideferrocyanide SolutionSolution colourcolour appearsappears

•• Part 2+ potassium Part 2+ potassium thiocyanatethiocyanate Blood red Blood red FeFe3+3+ is confirmed.is confirmed.

coloration appearscoloration appears

•• White gelatinous White gelatinous pptppt dissolvedissolve

•• in dil. in dil. HClHCl + + NaOHNaOH solutionsolution White gelatinous White gelatinous AlAl3+3+ is confirmed.is confirmed.

pptppt soluble in excesssoluble in excess

Analysis of Group IV Analysis of Group IV cationscations: (Zn: (Zn2+2+, Mn, Mn2+2+,Ni,Ni2+2+, and , and CoCo2+2+))

•• Dissolve the white Dissolve the white pptppt inin White White PPtPPt soluble soluble ZnZn2+2+ is confirmed.is confirmed.dil. dil. HClHCl and boiland boil in excessin excess+ + NaOHNaOH solution.solution.

•• Dissolved the flesh Dissolved the flesh pptppt inin White White pptppt MnMn2+2+ is confirmed.is confirmed.dil. dil. HClHCl and boil and boil which turns brownwhich turns brown+ excess + excess NaOHNaOH solution. solution.

•• Dissolve the black Dissolve the black pptppt in aqua in aqua regiaregia heat the solution to dryness and cool. Dissolve the residue in water and heat the solution to dryness and cool. Dissolve the residue in water and divide the solution into two Parts.divide the solution into two Parts.

•• To first part + NHTo first part + NH44OH more +OH more +few drop of few drop of dimethyldimethyl glyoximeglyoxime(DMG)shake(DMG)shake Bright red Bright red pptppt NiNi2+2+is confirmed.is confirmed.

•• To second part+ NHTo second part+ NH44OH +OH +acticactic acid+ solid KNOacid+ solid KNO22.. Yellow Yellow pptppt CoCo2+2+ is confirmed.is confirmed.

Analysis of Group V Analysis of Group V cationscations: (Ba: (Ba2+2+, Sr, Sr2+ 2+

and Caand Ca2+2+))

•• Dissolve the Dissolve the pptppt by boiling with dil. Acetic acid and divide the solution into three parts.by boiling with dil. Acetic acid and divide the solution into three parts.

•• First part + potassium First part + potassium

ChromatesolutionChromatesolution yellow yellow pptppt BaBa2+2+is confirmed.is confirmed.

•• FLAME TESTFLAME TEST

Paste of salt in conc. Paste of salt in conc. HClHCl is held is held

on the Bunsen flameon the Bunsen flame grassy green flame grassy green flame BaBa2+2+ is confirmed.is confirmed.

•• second part + (NHsecond part + (NH44))22SOSO44 solutionsolution White White pptppt SrSr2+2+ is confirmedis confirmed•• second part + (NHsecond part + (NH44))22SOSO44 solutionsolution White White pptppt SrSr2+2+ is confirmedis confirmed

Heat and scratch the side of the Heat and scratch the side of the

TesTes t tube with glass rod.t tube with glass rod.

•• FLAME TESTFLAME TEST

•• Paste of salt in conc. Paste of salt in conc. HClHCl is held is held

on the Bunsen flameon the Bunsen flame Crimson red flame Crimson red flame SrSr2+2+ is confirmed.is confirmed.

•• Third part + ammonium oxalateThird part + ammonium oxalate

Solution shake wellSolution shake well White White pptppt CaCa2+2+ is present.is present.

•• FLAME TESTFLAME TEST

•• Paste of salt in conc. Paste of salt in conc. HClHCl is held is held

on the Bunsen flameon the Bunsen flame Brick red flame Brick red flame CaCa2+2+ is confirmed.is confirmed.

Analysis of Group VI Analysis of Group VI cationcation(Mg(Mg+2+2))

•• If Group V is absent then perform the test If Group V is absent then perform the test for Mgfor Mg+2++2+ ions.ions.

•• OS+NHOS+NH44OH OH White White pptppt MgMg+2+2 is is +Na+Na22HPOHPO44 Solution Solution confirmedconfirmed

Titrimetric analysisTitrimetric analysis

Aim:Aim:-- Preparation of 250 mL of 0.1M Standard Preparation of 250 mL of 0.1M Standard solution of Oxalic acid. solution of Oxalic acid.

•• Theory:Theory:

•• Hydrated oxalic acid is dibasic weak acid and its molar mass is 126 g. If Hydrated oxalic acid is dibasic weak acid and its molar mass is 126 g. If 126g of oxalic acid is present in one liter of the solution It is known as one 126g of oxalic acid is present in one liter of the solution It is known as one molar (1.0M) solution. There for preparing 250mL of 0.1M oxalic acid molar (1.0M) solution. There for preparing 250mL of 0.1M oxalic acid solution, we required: solution, we required: 126g x 0.1M x 250mL/ 1000mL126g x 0.1M x 250mL/ 1000mL =3.1500g of =3.1500g of hydrated oxalic acid.hydrated oxalic acid.hydrated oxalic acid.hydrated oxalic acid.

•• In general for preparing a solution of required In general for preparing a solution of required molaritymolarity, the amount of , the amount of substance to be weighed can be calculated by using the formula given substance to be weighed can be calculated by using the formula given below:below:

Mass of solute in grams(m) x 1000Mass of solute in grams(m) x 1000

MolarityMolarity (M) = (M) = --------------------------------------------------------------------------------------------------------------------------------------------------------------------------

Molar mass of solute x vol. of solution to be prepared in Molar mass of solute x vol. of solution to be prepared in mLmL(v)(v)

Procedure:Procedure:•• Weigh an empty watch glass accurately. Then Weigh an empty watch glass accurately. Then weigh 3.1500g oxalic acid on the above watch weigh 3.1500g oxalic acid on the above watch glass. Transfer oxalic acid carefully from the glass. Transfer oxalic acid carefully from the watch glass into a clean measuring flask using watch glass into a clean measuring flask using a funnel. Weigh the empty watch glass again a funnel. Weigh the empty watch glass again and find out the mass of oxalic acid and find out the mass of oxalic acid transferred to the measuring flask. Wash transferred to the measuring flask. Wash transferred to the measuring flask. Wash transferred to the measuring flask. Wash funnel several times with distilled water by funnel several times with distilled water by using a wash bottle to transfer the sticking using a wash bottle to transfer the sticking particles. Swirl the measuring flask till solid particles. Swirl the measuring flask till solid oxalic acid is completely dissolved Add more oxalic acid is completely dissolved Add more distilled water to make up the volume with distilled water to make up the volume with distilled water up to the mark by adding last distilled water up to the mark by adding last few few mLmL drop wise. Stopper the flask and shake drop wise. Stopper the flask and shake it thoroughly to make the solutionit thoroughly to make the solution

Aim:Aim:-- Determination of the concentration( strength) of a Determination of the concentration( strength) of a given sodium hydroxide solution by tritrating it against a given sodium hydroxide solution by tritrating it against a standard solution of oxalic acid.standard solution of oxalic acid.

•• Reaction:Reaction:COOHCOOH COONaCOONaCOOHCOOH + 2NaOH + 2NaOH ------�� COONa + 2H2O.COONa + 2H2O.

•• Procedure:Procedure:

Wash the burette with distilled water and rinse the burette with sodium Wash the burette with distilled water and rinse the burette with sodium Wash the burette with distilled water and rinse the burette with sodium Wash the burette with distilled water and rinse the burette with sodium hydroxide solution. Then fill sodium hydroxide solution into the burette through a hydroxide solution. Then fill sodium hydroxide solution into the burette through a funnel above the zero mark.funnel above the zero mark.

Remove the air gap, if any from the nozzle of the burette and remove the Remove the air gap, if any from the nozzle of the burette and remove the funnel Note the initial reading by keeping the eye exactly at the same level as the funnel Note the initial reading by keeping the eye exactly at the same level as the lower meniscus of the solution.lower meniscus of the solution.

Pipette out 10mL of oxalic acid solution in a clean conical flask. Add 1Pipette out 10mL of oxalic acid solution in a clean conical flask. Add 1--2 drops 2 drops of phenolphthalein indicator to the conical flask. Titrate the acid with sodium of phenolphthalein indicator to the conical flask. Titrate the acid with sodium hydroxide solution till a very faint permanent pink colour is obtained. Read the lower hydroxide solution till a very faint permanent pink colour is obtained. Read the lower meniscus of the solution in the burette and note down.meniscus of the solution in the burette and note down.

Repeat the procedure until three concordant readings are obtained. Repeat the procedure until three concordant readings are obtained.

•• TableTable

•• Calcuation:Calcuation:•• Molarity of NaOH solution can be calculated by using the equation:Molarity of NaOH solution can be calculated by using the equation:

Oxalic aidOxalic aid Sodium hydroxideSodium hydroxideaa11MM11VV11 == aa22MM22VV22

Where, MWhere, M11 and Vand V11 are the molarity and volume of the oxalic acid, aare the molarity and volume of the oxalic acid, a11 is basicity of oxalic is basicity of oxalic Where, MWhere, M11 and Vand V11 are the molarity and volume of the oxalic acid, aare the molarity and volume of the oxalic acid, a11 is basicity of oxalic is basicity of oxalic acid =2acid =2

MM22 and Vand V22 are the molarity and volume of the sodium hydroxide solutio0n ,aare the molarity and volume of the sodium hydroxide solutio0n ,a22 is is acidity of sodium hydroxide solution =1acidity of sodium hydroxide solution =1

Calculate the concentrqatiuon of sodium hydroxide solution in g/L.Calculate the concentrqatiuon of sodium hydroxide solution in g/L.

Concentration (strength) in g/L = Molartity x Molar mass.Concentration (strength) in g/L = Molartity x Molar mass.

Result: Result:

The concentration of the given NaOH solution is ________ g/LThe concentration of the given NaOH solution is ________ g/L

Aim:Aim:-- preparation of 0.1M slandered preparation of 0.1M slandered

solution of sodium carbonate.solution of sodium carbonate.

•• Theory:Theory:

•• Molar mass of dry sodium carbonate is 106g. To prepare Molar mass of dry sodium carbonate is 106g. To prepare 0.1M Na0.1M Na22COCO33 solution, 10.6000g of sodium carbonate solution, 10.6000g of sodium carbonate should be dissolved per liter of the solution.should be dissolved per liter of the solution.

22 33

should be dissolved per liter of the solution.should be dissolved per liter of the solution.

•• There fore to prepare 100 mL of 0.1M NaThere fore to prepare 100 mL of 0.1M Na22COCO33 solution solution 1.0600g of sodium carbonate is dissolved in minimum 1.0600g of sodium carbonate is dissolved in minimum quantity of water and the solution id diluted exactly quantity of water and the solution id diluted exactly 100 mL by adding water.100 mL by adding water.

Procedure:Procedure:

•• Weigh an empty watch glass accurately. Then weigh Weigh an empty watch glass accurately. Then weigh 1.0600g Sodium carbonate on the above watch glass. 1.0600g Sodium carbonate on the above watch glass. Transfer Sodium carbonate carefully from the watch Transfer Sodium carbonate carefully from the watch glass into a clean measuring flask using a funnel. Weigh glass into a clean measuring flask using a funnel. Weigh the empty watch glass again and find out the mass of the empty watch glass again and find out the mass of Sodium carbonate transferred to the measuring flask. Sodium carbonate transferred to the measuring flask. Sodium carbonate transferred to the measuring flask. Sodium carbonate transferred to the measuring flask. Wash funnel several times with distilled water by using a Wash funnel several times with distilled water by using a wash bottle to transfer the sticking particles. Swirl the wash bottle to transfer the sticking particles. Swirl the measuring flask till solid Sodium carbonate is completely measuring flask till solid Sodium carbonate is completely dissolved Add more distilled water to make up the dissolved Add more distilled water to make up the volume with distilled water up to the mark by adding last volume with distilled water up to the mark by adding last few few mLmL drop wise. Stopper the flask and shake it drop wise. Stopper the flask and shake it thoroughly to make the solution.thoroughly to make the solution.

Aim:Aim:-- Determination of the strength of a given solution of Determination of the strength of a given solution of dilute hydrochloric acid by titrating it against a standard dilute hydrochloric acid by titrating it against a standard solution of sodium carbonate.solution of sodium carbonate.

•• Reaction:Reaction:

NaNa22 COCO33 + 2HCl + 2HCl --�� 2 NaCl + H2 NaCl + H22O + COO + CO22

•• Procedure:Procedure:Wash the burette with distilled water and rinse the burette with Wash the burette with distilled water and rinse the burette with Wash the burette with distilled water and rinse the burette with Wash the burette with distilled water and rinse the burette with

hydrochloric acid solution. Then fill hydrochloric acid solution into the hydrochloric acid solution. Then fill hydrochloric acid solution into the burette through a funnel above the zero mark.burette through a funnel above the zero mark.

Remove the air gap, if any from the nozzle of the burette and remove Remove the air gap, if any from the nozzle of the burette and remove the funnel Note the initial reading by keeping the eye exactly at the same the funnel Note the initial reading by keeping the eye exactly at the same level as the lower meniscus of the solution.level as the lower meniscus of the solution.

Pipette out 10mL of Sodium carbonate solution in a clean conical Pipette out 10mL of Sodium carbonate solution in a clean conical flask. Add 1flask. Add 1--2 drops of Methyl orange indicator to the conical flask. Titrate 2 drops of Methyl orange indicator to the conical flask. Titrate the Base with hydrochloric acid solution till Colour changes from yellow to the Base with hydrochloric acid solution till Colour changes from yellow to pinkishpinkish--red colour is obtained. Read the lower meniscus of the solution in red colour is obtained. Read the lower meniscus of the solution in the burette and note down.the burette and note down.

Repeat the procedure until three concordant readings are obtained. Repeat the procedure until three concordant readings are obtained.

•• TableTable

•• Calculation:Calculation:•• Molarity of HCl solution can be calculated by using the equation:Molarity of HCl solution can be calculated by using the equation:

HCl solutionHCl solution Na2CO3 solutionNa2CO3 solutiona1 M1 V1 a1 M1 V1 == a2 M2 V2a2 M2 V2

Where, Where, MM11 and Vand V11 are the molarity and volume of the HCl solution, a1 is basicity of HCl = 1are the molarity and volume of the HCl solution, a1 is basicity of HCl = 1

MM22 and Vand V22 are the molarity and volume of the sodium carbonate solution ,aare the molarity and volume of the sodium carbonate solution ,a22 is acidity is acidity Of sodium carbonate solution = 2Of sodium carbonate solution = 2

•• Calculate the concentration of hydrochloric acid solution in g/L.Calculate the concentration of hydrochloric acid solution in g/L.Molar mass of hydrochloric acid is 35.5 g molMolar mass of hydrochloric acid is 35.5 g mol--11

Concentration (strength) of HCl solution in g/L = Molartity x Molar mass.Concentration (strength) of HCl solution in g/L = Molartity x Molar mass.

Result: Result:

The concentration of the given HCl solution is ________ g/LThe concentration of the given HCl solution is ________ g/L