Advanced physical chemistry experiments

533 Pages·23.128 MB·English

by  J.N. Gurtu, Amit Gurtu.

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ADVANCED
PHYSICAL CHEMISTRY
EXPERIMENTS
Dr. J.N. Gurtu
M.Sc., Ph.D.
Former Principal
Meerut College, Meerut
Amit Gurtu
B. Tech., P. G.D.M.
~PRAGATI
PRAKASHAN
PRAGATI PRAKASHAN
Educational Publishers
Head Office: Revised and Enlarged Edition: 2008
PRAGATI BHAWAN
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CONTENTS
1. IMPORTANT FACTS IN EXPERIMENTAL CHEMISTRY 1-10
2. ERROR ANALYSIS AND STATISTICAL DATA ANALYSIS 11-25
3. ELECTRONICS 26-73
1. To measure the resistance with a multimeter. 26
2. To measure the output voltage of the audio signal generator with the help of
~O. V
3. To become familiar with CRO. 29
4. To use a Wheatstone bridge for the accurate measurement of resistance. 31
5. To study the charge and discharge of a capacitor through a resistor. 32
6. To study the responce characteristics of RC network 35
7. To study the response characteristics of LR network. 36
8. To verify the Kirchoff's current law (KCL). 37
9. To verify the Kirchoff's voltage law (KVL). 38
10. (1) To obtain Lissajous pattern on the CRO screen by feeding two sine-wave
voltage from two signal generators.
(2) To measure the frequency and phase shift by Lissajous pattern. 40
11. To determine the V-I characteristics of a given diode in : 42
(a) Forward biased mode/junction. (b) Reverse biased mode/junction.
12. To use the clamping and clipping circuits. 44
13. To study half-wave and a full-wave rectifier circuit with and without capacitor
filter and determine the ripple factor. 45
14. To determine the common base and common emitter characteristics of a
transistor. 49
15. To design and construct the differential amplifier. 54
16. To:
(i) Trace the circuit diagram of single stage transistor amplifier
(ii) Measure the 0 point collector current and collector-to-emitter voltage.
(iii) Measure the maximum signal which can be amplified by the amplifier
without having clipped output.
(iv) Measure the voltage gain of the amplifier at 1 kHz
(v) Measure the voltage gain of the amplifier for different values of load
resistance. 56
17. To study the introduction of an operational amplifier as a voltage follower. 58
18. 'lb design operational amplifier as inverting and non-inverting amplifier. 59
19. 'fo find t.he integration and differentiation with operational amplifier. 60
20. To study operational amplifier in (a) inverting mode (summing amplifier) (b)
non-inverting mode (c) integrator (d) differentiator (e) difference amplifier. 61
21. To determine the energy band gap of a semiconductor (germanium) using four
probe method. 66
22. To study the characteristics of an integrating and differentiating circuits. 70
23. 'lb observe wave-forms and to measure amplitude, frequency and phase with
a cathode ray oscilloscope. 71
(viii)
4. MOLECULAR WEIGHT OF VOLATILE LIQUIDS 74-83
1. To determine the molecular weight of the volatile liquid (chloroform, acetone,
methanol) by Victor Meyer's method. 76
2. To determine the composition or a binary mixture of liquids by Victor Meyer's
method. 80
3. To determine the solubility of CS2 In CH30H at room temperature. 80
4. To find out the molecular weight of the given liquid by steam distillation method. 81
5. To determine the vapour pressure of chlorobenzene by steam distillation. 83
5. CRYOSCOPY (DEPRESSION IN FREEZING POINT) 84-101
1. To find out the molecular weight of the given solute in water by depression in
freezing pOint method. 86
2. To find out the concentration of the given solution of urel'!. in water. 89
3. To find the molecular weight of sulphur, a-naphthol and biphenyl by freezing point
method uSing napthalene as solvent. 90
4. To find out the degree of dissociation of calcium nitrate. Also find its van't Hoff
factor. 91
5. To find out the pH of the given 0·1 N oxalic acid solution. 92
6. To find out the degree of association of benzoic acid in benzene. 93
7. To find out the degree of hydrolysis of the given substance, say CH COONa in
3
0·5M solution. 93
8. To study the formation of complex ions in solution of mercuric iodide in potassium
iodide solution. 94
9. To find out the molecular weight of the given substance by Rast's Camphor
method. 96
10. To determine the relative strength of acids. 96
11. To determine the dissociation constant of acetic acid in aqueous solution near
O·C. 97
12. To determine the latent heat of fusion per gram of ice (Lf) 97
13. To determine van't Hoff factor and find the apparent degree of association of
benzoic acid and acetic acid in 1M and 0.5M solutions of benzene, near the
freezing point of the liquid. 97
14. To analyse cryoscoplcally a given mixture of urea and glucose. 98
15. To determine K value of a given solvent. A solute of known molecular weight is
f
provided. 98
16. To verify the formula of the complex salts like K2S20S' K4Fe(CN)6 cryoscopicaliy. 98
17. To determine the mean activity coefficient of an electrolyte (NaCI) in dilute solution
by cryscopic measurements. 99
6. EBULLIOSCOPY (ELEVATION OF BOILING POINT) 102-109
1. To find the molecular weight of the given solute in water by elevation of boiling
point method. 104
2. To find out the concentration of the given solution of urea in water by elevation in
boiling point method. 105
3. To find out the degree of dissociation of an electrolyte. Also find its van't Hoff
factor. 106
4. To find out the ebuliioscopic constant of water by taking a known substance. 107
5. To find out the molecular weight of a solute by Cottrell's method. 108
(ix)
6. To determine the latent heat of evaporation. 109
7. To determine the pH of an acid, say oxalic acid (or malonic aCId). 109
8. To study the association of organic acids and hydroxy compounds in benzene and
other solvents. 109
7. VISCOSITY 110-121
1. To find the relative and absolute viscosity of the given liquid at the room
temperature. 114
2. To find the concentration of the given mixture, consisting of two liquids A and B
by viscosity measurements. 115
3. To find out the temperature coefficient for the given liquid. 116
4. To determine the influence of temperature on viscosity. 118
5. To calculate the molecular weight of a high polymer by means of viscosity
measurements. 118
6. To determine by viscosity method, whether the following pairs of liquids form
molecular compounds or not :
(a) Water and ethyl alcohol. (b) Methyl alcohol and ethylidine chloride. (c) Nitric
acid and chloroform. (d) Benzene and ethyl alcohol. 120
7. To study the variation of viscosity with composition of the mixture of water and
ethanol. 120
8. To determine the viscosity of different mixtures of benzene and nitrobenzene and
also test the validity of Kendall's equation. 121
8. SURFACE TENSION 122-145
1. To find the surface tension of the given liquid by drop weight method at room
temperature. 126
2. To find the composition of the given mixture of two components A and B. 127
3. To find out the surface tension of the given liquid by single capillary rise method. 128
4. To find out the surface tension of the given liquid by double capillary rise
method. 129
5. To find out the surface tension of CH 0H, C H 0H n-hexane at room
3 2 5
temperature and hence calculate the atomic parachors of C, Hand 0. 130
6. To find out the parachor of a solid in a given solvent by double capillary rise
method, assuming the mixture law to hold good. 131
7. To find out the molecular sUlface energy and the association factor ofC2HsOH. 132
I
8. To find out the parachor of a solid (say p-dichlorobenzene) in a given solvent
(say benzene! by double capillary rise method, assuming the mixture law to
hold good. 134
9. To find out the molecular surface energy and the association factor of ethyl
alcohol. 135
10. To study the change of surface tension of a mixture of ethanol and water with
composition by torsion balance method. 138
11. To find the surface excess or molar surface area by using Gibb's adsorption
equation 142
12. To determine the critical miscelle concentration of soap. 142
13. To show that surface activity of alcohol increases with chain length. 143
14. '1'0 determine the interfacial tension between benzene and water at room
temperature and test the validity of Antonoff's rule. 144
15. To compare the cleansing powers of two samples of detergents supplied to you. 144
(x)
9. VAPOUR PRESSURE OF LIQUIDS 146-151
1. To determine the vapour pressure of a pure liquid, say benzene at a series of
temperature and also determine the heat of vaporisation of liquid. 147
2. To determine the vapour pressure of water at different temperatures using Smith
and Menzies apparatus. 148
3. To determine tr.e vapour pressure of benzene at different temperatures by
Ramsay·Young apparatus. Also determine latent heat of vaporisation. 149
4. To study the variation of vapour pressure of a liquid (benzene) using an
isoteniscope. 151
10. SOLUBILITY 152-167
1. To determine the solubility of a given salt at room temperature and also draw its
solubility curve. 154
2. To find out the heat of solution of a substance, say oxalic acid by solubility method. 156
3. To determine the solubility of an organic acid at 40' and at a temperature lower
than the room temperature. 157
4. To determine the solubility product of Ca(OH)2 at room temperature. 158
5. To study the variation of the solubility of Ag8r03 in K8r03 solution and to
determine the solubility product of Ag8r03· 159
6. To study the effect of ionic strength on the solubility of CaS0 and so determine
4
its thermodynamic solubility product and mean ionic activity. 150
7. To study the variation of solubility of potassium hydrogen tartrate with ionic
strength using a salt having a common ion and thereby determine the mean ionic
activity coefficients. 162
8. To determine the solubility of oxygen in water at room temperature. 164
9. To study the influence of tho addition of various substances on the solubility of
solutes. 165
10. To study the effect of concentration of an electrolyte such as KCI, NaCI,
Na2S04, K2S04 on the solubility of an organic acid (benzoic acid or salicylic acid)
at room temperature. 165
11. To study the variation of solubility of Ca(OH)2 in NaOH solution and also to
determine its solubility product. 166
11 TRANSITION TEMPERATURE 168-174
•
1. To find out the transition temperature of Glauber's salt by dilatometric
method 169
2. To find od the transition temperature of Glauber's salt by solubility method. 171
3. '1'0 find out the transition temperature of Glauber's salt by thermometric
method. 172
4. To detenninc the transition temperature of double chloride of copper and
potassium. 174
5. To determine the transition of temperature of mercuric iodide. 174
6. To determine the transition temperature of sulphur system. 174
12. PARTITION COEFFICIENT 175-191
1. To find out partition coefficient of 12 between CCIt! and H20. 176 ~
2. To find out the partition coefficient of benzoic acid between C6H6 and water. 178
3. To find out the dimerisation constant of benzoic acid in benzene medium. 180
(xi)
4. To find out the equilibrium constant for the tri-iodide formation, 12 + 1-= Ii 182
5. To study the complex formation and find the formula of silver ammine complex by
partition method. 185
6. To find the formula of complex cuprammonium ion or study the complex formation
between CUS04 and NH3 solution. 187
7. To determine the partition coeficient of succinic acid between water and ether. 189
8. To determine the molecular weight of succinic acid in benzene by determining
its partition coefficient with water. 190
9. Study the paltition of salicylic acid or picric acid between water and benzene
and between water and chloroform. 190
10. Find out the dimerisation constant of phthalic acid in a suitable solvent of
your choice. 190
11. Find out the partition coefficient of acetic acid between water and cyclohexane
or butanol. 191
12. Find out the molecular state of benzoic acid in benzene and water. 191
13. COLLOIDS 192-201
1. To prepare colloidal solutions of As2S3, Sb2S3 and Fe(OH)3' 193
2. To find out the precipitation valu{,s of As2S3 sol by using monovalent, bivalent
and trivalent cations. Also test the validity of Schulze-Hardy law and
Freundlich's adsorption isotherm. 195
3. To investigate the nature of charge on particles in a given colloidal solution ...
and determine their electrophoretic velocity and zeta potential. 198
4. To find out the precipitation values of a number of active ions for a ferric hydroxide
solution. 200
5. To find out the effect of electrolytes on the viscosity of a gelatin gel. 200
6. To find out the effect of concentration of an electrolyte on the viscosity of a gelatin
gel. 200
7. To study the effect of gelatin solution on the precipitation values of NaCI and BaCI
2
for silver sol. 200
8. To study the protective action of a hydrophilic colloid (such as starch, gelatin) on the
precipitation of lyophobic sols. 201
9. To study the mutual coagulation of AS2S3 solution and Fe(OH)3 solution and
determine the optimum ratio for precipitation. 201
14. ADSORPTION 202-209
1. Study the adsorption of acetic acid on charcoal and prove the validity of
Freundlich's adsorption isotherm and Langmuir's adsorption isotherm. 202
2. To determine the surface area of the given powdered catalyst sample by means
of BET adsorption isotherm. 204
3. To study the adsorption of iodine from alcoholic solution on charcoal. 208
4. To study the adsorption of oxalic acid on charcoal and test the validity of
Langmuir's and Freundlich's adsorption isotherm. 209
5. To study the effect of temperature on adsorption. 209
6. To study the adsorption of certain dyes such as methyl violet, picric acid or
malachite green on charcoal. 209
'. 15. PHASE EQUILIBRIUM 210-226
1. To draw the mutual solubility curve of two immiscible liquids and find out the C.S.T.
of phenol-water system 210
(xii)
2. Plot a graph for the miscibility temperature of mixture of 5 ml of 80% phenol and
5 ml of water in presence of 0·0 to 1·0% NaCI in aqueous layer in steps of 0·2%
and find the amount of NaCI in the given solution of NaCI of unknown percentage. 212
3. Determine the compositions and the amounts of the layers obtained by mixIng
55g of CeHsOH and 45 g of H20 at any temperature. 213
4. Study the boiling POInt-composition, curve for the binary liquid mixture of two
miscible liquids. 214
5. Study the bOIling point-composItion curves for binary liquid mIxtures. 215
6. Study the boiling point-compoSItIon curves for systems of bInary liquid mixtures. 216
7. Draw a phase diagram for lead and tin and from it find out the melting points of
the two components. Find the eutectic temperature also. 216
8. To determine the phase diagram of naphthalene and diphenyl system. 219
9. To determIne the freezing point diagram of o-nitrophenol and p-toluidine system. 219
10. To construct a phase diagram for a two component system by plotting cooling
curves for mixtures of different compositions. 219
11. To obtain the phase diagram for water-ethanol-benzene system at room
temperature. 221
12. To study the mutual solubility and determine the upper and lower consolute
temperatures of (a) nicotine-water system (b) glycerol-m-toluidine system. 223
13. To study the mutual solubility of triethyl amine-water system and find the critical
solution temperature. 223
14. Construct a phase diagrams for: (a) urea (m. pt. 132"C) and phenol (m. pt. 43"C)
system, (b) a-naphthyl-amine-phenol system. 223
15. Determine the freezing point curve of picric acid-benzene system. 223
16. To obtain a solubility curve for a ternary system of liquids, say water-acetic
acid-chloroform system. 224
17. To study the influence of impurity on a ternary mixtur8. 226
18. To study the miscibility curve of a ternary system at different temperatures, by
taking water-acetic acid-benzene. 226
19. Construct the phase diagram of three component system containing ethanol,
benzene and water. 226
16. THERMOCHEMISTRY 227-246
1. To find the water equivalent of the calorimeter and also find out the heat of dilution
of H2SO4, 229
2. To find out the heat of neutralisation of NaOH and HC\. 230
3. To determine the heats of neutralization of two acids, e.g., HCI and CH COOH
3
and hence their relative strength. 233
4. To find the heats of reaction for the reactions:
(a) HC204 + H20 ~ H2C204 + OW
(b) CO§" + H20 ~ HC03 + OH" 233
5. To determine the basicity of a polybasic acid of molecular weight 126. Also obtain
the heat of neutralisation for the different stages of neutralisation. 234
6. To find out the heat of neutralisation of HAc by NaOH and from it also calculate
the heat of ionisation of HAc. 235
7. To find out the heat of solution of a given substance. 236
.'
8. To determine integral heats of dilution of H2S04 starting with 10M acid and going
down to 5M acid in the order 9M, 8M, 7M, 6M. 237
9. To determIne the heats of formation of MgO and ZnO calorimetrically. 238
(xiii)
10. To determine the enthalpy change for the precipitation of a mole of Cu or Ag by
ln, Fe or Mg powder. 239
11. To find out the heat of precipitation of Agl. 240
12. To determine the fuel value of the given fuel by using a bomb calorimeter. 241
13. To determine the heat of hydration of anhydrous copper sulphate. 243
14. To determine the heat of hydration of sodium carbonate (Na2C03·10H20). 244
15. To determine the heat of solution at various temperatures. 244
16. To determine the integral heat of solution of a salt at two concentrations and hence
the integral heat of dilution. 244
17. To determine the heat of neutralisation of acetic acid by ammonium hydroxide. 245
18. To determine the heat of precipitation of BaS04' 245
19. To determine the heat of transition of Na2S04.10H20 by calorimetry. 246
17. REFRACTOMETRY 247-255
1. To find out the refractive index of the given liquid and also find its molecular
refractivity. 249
2. To find out the molecular refractivities of three liquids A, Band C. Also calculate
the composition of the liquid C, which is a mixture of two liquids A and B. 250
3. To find out the atomic refractivities of C, Hand 0, by taking methyl acetate, ethyl
acetate and n-hexane as the experimental liquids. 251
4. To determine the molecular refractivity of a solid. 252
5. To determine the refractive indices of a series of solutions of KCI and hence
determine the compositions of tho unknown solution of the salt. 253
6. To study the variation of refractive index with composition of mixtures of carbon
tetrachlonde and ethyl acetate. 253
7. You are provided with two liquids 1 and 2 and their mixtures 3 and 4. By means
of a refractometer find the compositions of 3 and 4. 254
8. To determine the molar refractions of ethyl acetate, propyl acetate and butyl acetate
and show the constancy of the contribution to the molar refraction made by -CH2
group. 254
9. To determine molar refractivity of ethyl acetate, methyl acetate, ethylene chloride
and chloroform and calculate the atomic refractivities of C, Hand CI. The density
of each liquid can be measured experimentally or seen from the table. 254
10. To measure refractometrically average polarizability of some of the common
solvents. 255
11. To calculate the value of optical exhaltation. 255
18. CHEMICAL KINETICS 256-293
1. To find the velocity constant of the hydrolysis of methyl acetate catalysed by an
acid. 264
2. To determine the order of saponification of ethyl acetate with NaOH. 266
3. To compare the strength of two acids say hydrochloric acid and sulphuric acid,
used in equal concentration for the hydrulysis of methyl acetate. 268
4. To study the reaction kinetics of decomposition of benzene diazonium chloride
in the temperature range 90'C to 60'C. Calculate the rate constant also. 269
5. To study the reaction between acetone and iodine in presence of acids. 270
6. To study the kinetic characteristics of iodination of acetone using a
colorimeter. 273
7. To find out the order of reaction between potassium bromate and potassium
iodide. 274