PRACTICAL CHEMISTRY for B.Sc. I Year GNDU, Punjabi & Panjab University (as per latest Syllabi) Dr. M.S. BATRA Dr. FATEH BAHADUR M.Sc., Ph.D. (B.H.U.) Ex. Head, Department of Chemistry K.N. Govt. P.G. College Gyanpur, Sant Ravidas Nagar, BHADOHI (U.P.) Dr. UPDESH KAUR Associate Prof. Associate Prof. Post-Graduate Department of Chemistry Khalsa College, AMRITSAR (An Autonomous College) Head, Department of Chemistry Kanya Maha Vidyalaya, JALANDHAR 2013-14 Future for WINNERS VISHAL PUBLISHING CO. JALANDHAR DELHI
CONTENTS Basic Laboratory Techniques 01 08 1. Working in a Chemical Laboratory / 1 2. Cleaning of the Glass Apparatus / 1 3. Dilution of the Concentrated Acids / 2 4. Analytical Balance / 2 5. Analytical Weights / 3 6. Weighing / 4 7. Flames / 5 8. Quantitative Transfer of a Substance to a Graduated Flask / 5 9. Instruments used for measuring Liquids and their Calibration / 6 Section 1. QUALITATIVE INORGANIC ANALYSIS Chapter 1. Physico Chemical Principles Involved in Qualitative Analysis 11 16 1.1 Law of Mass Action / 11 1.2 Common Ion Effect / 11 1.3 Solubility Product / 12 Application of Solubility Product in Qualitative Analysis / 13 1.4 Hydrogen Ion Concentration and ph / 15 Chapter 2. Semi-Micro Analysis of Mixture 17 30 2.1 Semi-Micro Apparatus / 17 1. Test tubes and centifuge tubes / 17 2. Stirring rods / 17 3. Dropper / 19 4. Reagent bottles / 19 5. Test-tube holder / 19 6. Cleaning of apparatus / 20 7. Centrifuge / 20 8. Detection of the evolved gases / 20 9. Heating of the solution / 22 10. Warming of the solution / 22 11. Evaporation of the solution / 22 2.2 Analysis of Acid Radicals (Anions) / 23 Systematic Analysis / 23 2.3 Dry Tests or Preliminary Tests / 23 1. Physical Examination of Mixture / 24 2. Dry Heating Test / 24 3. Flame Test / 26 4. Borax-Bead Test / 27 5. Charcoal Cavity Test / 29 6. Cobalt Nitrate Test / 29 Chapter 3. Detection and Identification of Acid Radicals 31 40 3.1 Dilute Acid Test / 32
3.2 Reactions of Acid Radicals with Dil. H 2 SO 4 / 33 3.3 Concentrated Sulphuric Acid Test / 35 3.4 Reactions of Acid Radicals with Conc. H 2 SO 4 / 37 3.5 Tests for Sulphate, Phosphate and Borate / 39 3.6 Reactions in Special Test / 40 Chapter 4. Wet Tests for Acid Radicals (Confirmatory Tests for Anions) 41 45 4.1 Sodium Carbonate Extract or Soda Extract / 41 4.2 Advantages of Sodium Carbonate Extract / 41 4.3 Preparation of Sodium Carbonate Extract / 42 4.4 Test of Acid Radicals with Sodium Carbonate Extract / 42 1. Sulphate (SO 2 4 ) / 42 2. Sulphite (SO 2 3 ) / 42 3. Sulphide (S 2 ) / 42 4. Cloride (Cl ) / 43 5. Bromide (Br ) / 43 6. Iodide (I ) / 43 7. Nitrate (NO 3 ) / 44 8. Nitrite (NO 2 ) / 44 9. Oxalate (C 2 O 2 4 ) / 45 10. Acetate (CH 3 COO ) / 45 11. Phosphate / 45 Chapter 5. Tests for Combinations of Acid Radicals 46 52 5.1 Carbonate and Sulphite (CO 3 2 & SO 3 2 ) / 46 5.2 Carbonate and Oxalate (CO 3 2 & C 2 O 4 2 ) / 47 5.3 Sulphide, Sulphite and Sulphate or any two of these (S 2, SO 3 2 and SO 4 2 ) / 47 5.4 Nitrite and Nitrate (NO 2 & NO 3 ) / 49 Removal of Nitrite in the test of Nitrate / 49 5.5 Chloride, Bromide and Iodide (Cl, Br & I ) / 50 5.6 Nitrate and Bromide (NO 3 & Br ) / 51 5.7 Nitrate and Iodide (NO 3 & I ) / 52 Chapter 6. Wet Tests for Basic Radicals 53 78 6.1 Analysis of Basic Radicals / 53 6.2 Some Details about Groups of Cations / 53 6.3 Preparation of Original Solution / 55 6.4 Analysis of Individual Groups of Cations / 56 Zero Group / 56 First Group (Silver Group I) / 56 Second Group (II) / 59 Third Group (III) / 67 Fourth Group (IV) (Zinc Group) / 69 Fifth Group (V) (Calcium Group) / 72 Sixth Group (VI) / 74 6.5 Specimen of Recording Inorganic Mixture Analysis / 76 Chapter 7. Viva Voce Questions (Mixture Analysis) 79 88
Section 2. QUANTITATIVE ANALYSIS #Chapter 8. Volumetric Analysis 91 104 8.1 Volumetric Analysis or Titrimetric Analysis / 91 8.2 Titrations are of Four Types / 92 (1) Acid Base Titrations / 92 (2) Oxidation Reduction Titrations or Redox Titrations / 93 (3) Precipitation Titrations or Precipitimetry / 93 (4) Complex Formation Titrations or Complexometric Titrations / 94 8.3 Indicators / 94 (1) Internal Indicators / 94 (2) External Indicators / 94 (3) Self-Indicators / 95 8.4 Equivalent Weight / 95 8.5 Expression of Concentration / 100 (1) Percentage / 100 (2) Molality / 100 (3) Molarity / 101 (4) Normality / 102 (5) Formal Solution / 103 8.6 Standard Solution / 103 Primary Standard Substance / 103 Secondary standard substances or secondary standards / 103 Calculation of Volumetric Analysis / 104 #Chapter 9. Viva Voce Questions (Volumetric Analysis) 105 109 #Chapter 10. Volumetric Analysis involving Acid-Base and Redox Titrations 110 122 10.1 Acid Base Titrations (1) Experiment 10.1. Determine the strength of given Na 2 CO 3 solution. You are provided with N/20 HCl acid solution. / 110 (2) Additional Exercises / 112 10.2 Redox Titrations / 113 (1) Experiment 10.2. Find out molarity and strength of given KMnO 4 solution. You are provided with M/40 oxalic acid solution. / 113 (2) Experiment 10.3. Find out normality and strength of given oxalic acid solution. You are provided with N/20 KMnO 4 solution. / 116 (3) Additional Exercises / 117 (4) Viva Voce / 118 10.3 Potassium Dichromate Titrations / 118 (1) Experiment 10.4. Determine the strength of a given solution of potassium dichromate by titrating it against a standard solution of Mohr s Salt (M/20) / 118 (2) Additional Exercises / 120 (3) Viva Voce / 121
Section 3. ORGANIC CHEMISTRY LABORATORY TECHNIQUES *Chapter 11. Determination of melting and boiling points of Organic Compounds 125 130 11.1 Determination of Melting Point / 125 Experiment 1. Determine the melting point of given solid substance. / 125 11.2 Determination of Boiling Point / 128 (1) Boiling point / 128 (2) Siwoloboff's Method for determination of boiling point / 128 11.3 Viva-Voce / 129 Chapter 12. Crystallization 131 138 12.1 Crystallization / 131 12.2 Some Common Laboratory Glasswares / 131 12.3 Process of Crystallization / 131 (1) Experiment 1. Recrystallisation of Acetanilide from boiling water. / 135 (2) Experiment 2. Recrystallisation of benzoic acid from water. / 136 (3) Experiment 3. Recrystallisation of Naphthalene from ethanol. / 136 (4) Experiment 4. Recrystallization of Phthalic acid from hot water. / 137 12.4 Viva-Voce / 137 Section 4. PHYSICAL CHEMISTRY EXPERIMENTS Chapter 13. Chemical Kinetics 141 149 13.1 Rate of Reaction / 141 13.2 Factors Affecting the Rate of a Reaction / 141 13.3 Molecularity and Order of a Reaction / 141 13.4 First Order Reactions / 142 13.5 Pseudo-First Order Reactions / 143 13.6 Kinetics of Pseudo-First Order Reactions / 144 (1) Experiment 1. To determine the velocity constant of the hydrolysis of ethyl acetate (ester) at room temperature in the presence of HCl and show that the reaction is of first order. /145 (2) Experiment 2. To study the effect of acid strength on the rate of hydrolysis of ethyl acetate. / 147 13.7 Viva-Voce / 148 Chapter 14. Viscosity 150 159 14.1 Theory / 150 14.2 Ostwald's Viscometer / 151 14.3 Measurement of Density by Relative Density (R.D.) Method / 153 (1) Experiment 1. To determine the coefficient of viscosity of the given liquid at room temperature by Ostwald s viscometer. / 153 (2) Experiment 2. To determine the percentage composition of the given mixture consisting of two liquids A and B, (non interacting system) by viscosity method. / 158 14.4 Viva-Voce / 159 Chapter 15. Surface Tension 160 167 15.1 Surface Tension / 160 15.2 Determination of Surface Tension / 160 (1) Drop Weight Method / 160
(2) Experiment 1. To determine the surface tension of liquid by drop number method, at room temperature (by stalagmometer). / 162 (3) Experiment 2. To determine the percentage composition of given mixture of two components A and B by drop number method. (Surface Tension Method). / 165 (4) Experiment 3. To determine the surface tension of given liquid by drop weight method using stalagmometer. / 165 15.3 Viva-Voce / 166 =Chapter 16. Solubility 168 172 16.1 Solubility Experiment 1. To determine the solubility of benzoic acid at different temperatures and to determine H of the dissolution process. / 168 16.2 Viva-Voce / 171 =Chapter 17. Thermochemistry 173 184 17.1 Thermochemistry / 173 17.2 Heat of Reaction / 173 17.3 Calorimetry / 173 17.4 Heat of Solution / 173 17.5 Heat of Neutralization / 174 (1) Experiment 1. To determine the heat of neutralization of strong acid (HCl) and strong base (NaOH). / 175 (2) Experiment 2. To determine enthalpy of neutralization of weak acid e.g., acetic acid by strong base (sodium hydroxide) and also determine the enthalpy of ionisation of weak acid (acetic acid). / 177 (3) Experiment 3. To determine calorimetrically the enthalpy of neutralization of weak base (NH 4 OH) with a strong acid (HCl). Also determine the enthalpy of ionization of weak base. / 179 (4) Experiment 4. To determine the enthalpy of a solution of solid calcium chloride and calculate the lattice energy of calcium chloride from its enthalpy of solution (enthalpy data) using Born-Haber cycle. / 179 17.6 Viva-Voce / 182 vchapter 18. Molecular Weight Determinations 184 185 18.1 Rast's Camphor Method / 184 Experiment 1. To determine the molecular weight of a given substance using Rast's Camphor method. / 184 Appendices I to XI 186 199 # For Panjab University only * For GNDU & Punjabi University only = For GNDU only v For Punjabi University only