ENGINEERING CHEMISTRY CLASS NOTES

Sri Shridevi Charitable Trust( R ) SHRIDEVI INSTITUTE OF ENGINEERING AND TECHNOLOGY, TUMKUR-572106 ENGINEERING CHEMISTRY CLASS NOTES NAME : USN : BRANCH : SECTION : Dr CHANDRASEKHAR N H.O.D of chemistry Miss SUJATHA.K Miss SHWETHA S RAO SHRIDEVI INSTITUTE OF ENGINEERING AND TECHNOLOGY CONTENTS UNIT PAGE NO TITLE I CHEMICAL ENERGY SOURCES 04-24 II ELECTROCHEMICAL SYSTEMS 25-43 III CONVERSION AND STORAGE ELECTROCHEMICAL ENERGY IV CORROSION SCIENCE 57-71 V METAL FINISHING 72-84 VI LIQUID CRYSTALS APPLICATIONS VII HIGH POLYMERS VIII WATER TECHNOLOGY 116-132 MODEL QUESTION PAPER 133-140 IX ENERGY AND OF THEIR ENGINEERING CHEMISTRY DEPARTMENT, S.I.E.T., TUMKUR 44-56 85-98 99-115 SHRIDEVI INSTITUTE OF ENGINEERING AND TECHNOLOGY Syllabus PART A Unit - I Electrode Potential and Cells Introduction, Differentiation between galvanic and electrolytic cells, Construction of galvanic cell, EMF of a cell , Origin of single electrode potential, Sign convention and cell notation, Standard electrode potential, Derivation of Nernst equation for single electrode potential Types of electrodes: Reference electrodes – Primary and secondary , Limitations of standard hydrogen electrode, Construction and working of calomel electrode and Ag – AgCl electrode, Measurement of single electrode potential, Numerical problems on electrode potential and EMF of a cell, Ion selective electrode: Glass electrode – Construction , Determination of pH of a solution using glass electrode Hours Unit - II Batteries and Fuel Cells Basic concepts, Battery characteristics, primary, secondary, reserve batteries and super capacitors with examples Classical batteries: Construction, working and applications of Zn – MnO2 battery, Lead acid storage battery and Ni – Cd battery Modern batteries: Construction and working and applications of Zn – air, Ni – metal hydride and Li – MnO2 batteries Fuel cells – Differences between battery and fuel cell, construction and working of H2 – O2 and CH3OH– O2 fuel cells Hours Unit - III Corrosion and its control Electrochemical theory of corrosion, Galvanic series, Types of corrosionDifferential metal corrosion, Differential aeration corrosion(Pitting and water line corrosion) , Stress corrosion (caustic embrittlement in boilers), Factors affecting the rate of corrosion Corrosion control: Inorganic coatings – Anodizing and phosphating, Organic coating – painting, Metal coatings – Galvanizing and Tinning, Corrosion inhibitors, Cathodic protection Hours Unit – IV ENGINEERING CHEMISTRY DEPARTMENT, S.I.E.T., TUMKUR SHRIDEVI INSTITUTE OF ENGINEERING AND TECHNOLOGY Metal Finishing Technological importance, Theory of electroplating, Significance of Polarization, Decomposition potential and Overvoltage in electroplating Effect of plating variables on the nature of electrodeposit Electroplating process, Electroplating of Copper and Chromium Distinction between electroplating and electrolessplating, Electolessplating of copper and nickel Hours PART B Unit - V Chemical fuels and Photovoltaic cells Introduction, Classification of chemical fuels, Calorific value – High and Low calorific values, Determination of calorific value –solid or liquid fuel using Bomb calorimeter, Gaseous fuel using Buoy’s calorimeter, Numerical problems Petroleum – Cracking by fluidized catalytic cracking process, Reformation of petrol, Octane and Cetane numbers Knocking – mechanism and harmful effects Antiknocking agents – TEL, Catalytic converters – Principle and working, Unleaded petrol, Power alcohol and Biodiesel Photovoltaic cells – Production of solar grade silicon, Doping of silicon, Construction and working of photovoltaic cell, Advantages Hours Unit - VI The Phase rule and Instrumental methods of analysis Statement of Gibb’s phase rule and explanation of the terms involved, Phase diagram of one component system – water system, Condensed phase rule , Phase diagram of two component system- Eutectic Pb – Ag system and Fe – C system Application – Desilverization of lead Instrumental methods of analysis- Theory , Instrumentation and applications of Colorimetry, Potentiometry , Conductometry and Flame photometry Hours Unit - VII Polymers Types of polymerization – Addition and Condensation, Mechanism of polymerization – Free radical mechanism taking ethylene as example ENGINEERING CHEMISTRY DEPARTMENT, S.I.E.T., TUMKUR SHRIDEVI INSTITUTE OF ENGINEERING AND TECHNOLOGY Glass transition temperature ( Tg) Structure – property relationship Types of plastics – Thermosetting and thermoplastics Compounding resins to plastics, Manufacture of plastics by compression and injection moulding, extrusion method Synthesis and applications of Teflon, PMMA, Polyurethane and Phenol – formaldehyde resins Elastomers: Deficiencies of natural rubber, Vulcanization of rubber Synthesis and applications of Neoprene and Butyl rubber, Silicone rubbers Adhesives: Synthesis and applications of epoxy resins Polymer composites - Synthesis and applications of Kevlar and Carbon fibers Conducting polymers – Definition, Mechanism of conduction in Polyacetylene and Polyaniline Hours Unit - VIII Water Chemistry Impurities in water, Water analysis – Determination of different constituents in water – Hardness, alkalinity, chloride , fluoride , nitrate , sulphate and dissolved oxygen by Winkler’s method Numerical problems on hardness and alkalinity Sewage – BOD and COD, Numerical problems, Sewage treatment Desalination of water – Reverse Osmosis and Electrodialysis Hours Text Books A text book of Engineering Chemistry P.C Jain and Monica Jain Dhanpatrai Publications, New Delhi Chemistry In Engineering and Technology ( Vol &2) J.C Kuriacose and J Rajaram Reference Books Principles of Physical Chemistry B.R Puri , L.R.Sharma & M.S Pathania, S Nagin chand and Co Text Book of Polymer Science F.W Billmeyer John Wiley & Sons Corrosion Engineering M.G Fontana Mc Graw Hill Publications Environmental Chemistry Stanley E Manahan , Lewis Publishers Polymer Science V.R Gowariker , Wiley Eastern Ltd ENGINEERING CHEMISTRY DEPARTMENT, S.I.E.T., TUMKUR SHRIDEVI INSTITUTE OF ENGINEERING AND TECHNOLOGY U N IT – I CHEMICAL ENERGY SOURCES: FUELS 1.1 Define a fuel Explain the classification of fuels with examples Marks A fuel is defined as naturally occurring or artificially manufactured combustible carbonaceous material which serves particularly as source of heat and light and also in few cases as a source of raw material Classification of fuels Fuels are classified into a two types 1) Based on their origin they are classified into a) Primary fuels b) Secondary fuels a) Primary Fuels: There are naturally occurring fuels which serves as source of energy without any chemical processing Ex: Wood, Coal, Crude oil, Natural gas, Peat, Lignite, Anthracite b) Secondary Fuels: - They are derived from primary fuels & serves as source of energy only after subjecting to chemical processing Ex: Charcoal, Coke, produsergas, Petrol, Diesel etc., 2) Bases on their physical state fuel are classified into a) Solid b) Liquid c) Gaseous fuels SOLID LIQUID Primary Fuels Wood, Coal, Crude oil Peat, Anthracite Secondary Fuels Coke, Charcoal GASEOUS Natural gas LPG, Petrol, Gasoline, produsergas, Diesel Coal gas 1.2 Define Calorific Value Explain the types 04 Marks Calorific value is defined as the amount of heat liberated when a unit mass of fuel is burnt completely in presence of air or oxygen ENGINEERING CHEMISTRY DEPARTMENT, S.I.E.T., TUMKUR SHRIDEVI INSTITUTE OF ENGINEERING AND TECHNOLOGY Calorific value is of two types as follows:1) Higher calorific value (HCV) or Gross calorific value (GCV) 2) Lower calorific value (LCV) or Net calorific value (NCV) 1) HCV: - It is the amount of heat liberated when a unit mass of fuels burnt completely in the presence of air or oxygen and the products of combustion are cooled to room temperature Here it includes the heat liberated during combustion and the latent heat of steam Hence its value is always higher than lower calorific value 2) LCV: - It is amount of heat liberated when a unit mass of fuel is burnt completely in the presence of air or oxygen and the product of combustion are let off completely into air It does not include the latent heat of steam Therefore it is always lesser than HCV NCV = HCV – Latent heat of steam = HCV –0.09X % H2 X 587 cal/g 1.3 Mention the SI units of calorific value Marks In SI system the units of calorific values for solid fuels are expressed in J/Kg and for gaseous and liquid are expressed in J/m3 1.4 Explain the determination of calorific value of solid fuel using Bomb calorimetric method Marks ENGINEERING CHEMISTRY DEPARTMENT, S.I.E.T., TUMKUR SHRIDEVI INSTITUTE OF ENGINEERING AND TECHNOLOGY A small quantity of a fuel is weighed accurately (M Kg) and is placed in the Bomb The bomb is placed in known amount water taken in a copper calorimeter The initial temp of water is noted as a t10C with the help of thermometer Oxygen gas is pumped under pressure 20 to 25 atm through the O2 valve provided The fuel is ignited by passing electric current through the wires provided As the fuel undergoes combustion and liberates heat, which is absorbed by surrounding water The water is stirred continuously to distribute the heat uniformly and the final temp attained by water is noted t20C & gross calorific value of the fuel is calculated as follows:Calculation: Mass of the fuel = M Kg Initial temp of the water = t10C Final temp of the water = t20C Change in temp = t = (t2 – t1)0 C Specific heat of water = S Water equivalent of calorimeter = W Kg GCV = W x S x t J/Kg or M GCV = (W+w) x S x t J /Kg M NCV = GCV – 0.09 x %H2 x 587 cal/g PROBLEMS: 1) Calculate calorific value coal samples from the following data Marks Mass of the coal = 1g Water equivalent of calorimeter = Kg Specific heat of water = 4.187 J/Kg/c Rise of temperature = 4.80C Solution: GCV = W x S x t J/Kg M = x 4.187 x 4.8 0.001 = 40195.2 KJ/Kg ENGINEERING CHEMISTRY DEPARTMENT, S.I.E.T., TUMKUR SHRIDEVI INSTITUTE OF ENGINEERING AND TECHNOLOGY 2) A coal sample with 93% carbon, 5% of Hydrogen and 2% Ash is subjected to combustion in a bomb calorimeter Calculate GCV and NCV Given that Marks Mass of the coal sample = 0.95g Mass of water in copper calorimeter = 2000g Water equivalent wt of calorimeter = 700g Rise in temp = 2.80C Latent heat of = 587 cal/g Specific heat of water = cal/g/0C GCV = (W+w) x S x t M = (2000+700) x 10-3 kg x cal/g/0C x 2.80C x 4.184 0.95 x 10-3 kg = 33295.83 J/kg NCV = GCV – 0.09 x %H2 x 587x4.184 J/kg = 33295.83 J/kg – 0.09 x x 587 x4.184 = 32190.62 J/kg J/kg 3) When 0.84g of coal was burnt completely in Bomb calorimeter the increase in temp of 2655 grams of water was 1.850C if the water equivalent calorimeter is 156g Calculate GCV GCV = (W+w) x S x t M = (2655+156) x 1.85 x 10-3 x 4.187 0.84 x 10-3 = 25921.26 J/Kg 4) Calculate GCV and NCV of a fuel from the following data Mass of fuel=0.75g, W=350g t =3.020C, Mass of water = 1150, % H2=2.8 Marks GCV = (W+w) x txS M = (1150+350) x10-x3 3.02 x 4.184 0.75 x 10-3 GCV = 25271 36 KJ/Kg NCV = GCV –0.09 x H x 587 x 4.184 ENGINEERING CHEMISTRY DEPARTMENT, S.I.E.T., TUMKUR SHRIDEVI INSTITUTE OF ENGINEERING AND TECHNOLOGY = 25271.36 – 0.09 x 2.8 x 587 x 4.184 NCV = 24652.44 KJ/Kg 5) Calculate calorific value of a fuel sample of a coal form the following data Mass of the coal is 0.6g Water equivalent wt of calorimeter is 2200g Specific value 4.187 Kg/KJ/C rise in temperature = 6.520C Marks GCV = (W1+W2) x S x t M = (2200) x 10-3 x 4.184 x 6.52 0.6 x 10-3 = 100025.49 KJ/Kg 6) Calculate GCV and NCV of a fuel from the following data Mass of fuel =0.83g, W=3500g , W = 385 g, t1 =29.20C, t2 = 26.50C, % H2 = 0.7 and S = 4.2 kj/kg/c Marks GCV = (W+w) x txS M = (3.5 + 0.385) x (29.2 – 26.5) x 4.2 0.83 x 10-3 GCV = 53079.39 KJ/Kg NCV = GCV –0.09 x H x 587 x 4.184 = 53079.39 – 0.09 x 0.7 x 587 x 4.2 NCV = 52924.07 KJ/Kg ENGINEERING CHEMISTRY DEPARTMENT, S.I.E.T., TUMKUR SHRIDEVI INSTITUTE OF ENGINEERING AND TECHNOLOGY The removal of course solids in the sewage water is effected by means of racks, screens, grid chambers & skimming tanks Then the water is passed into a sedimentation tank where it is allowed to settle The non-settle able solids are removed by coagulation by treatment with coagulating agents like alum, ferric chloride or lime b) Secondary treatment.( Activated sludge process ) The waste water after the primary treatment is allowed to flow into large tanks where biological treatment is carried out Activated sludge containing microorganisms is sprayed over the water The microorganisms present in the sludge form a thin layer & thrive on the organic wastes in the sewage Air is passed vigorously passed from the center of the tank in order to bring good contact between the organic wastes & bacteria in presence of air & sunlight Under these conditions, aerobic oxidation of organic matter occurs The sludge formed is removed by settling or filtration A part of the sludge is reused & the rest is used as fertilizer The residual water is chlorinated to remove bacteria & finally discharged into running water or used for watering plants The activated sludge process operates at 90-95percent efficiency of BOD treatment If the treated water contains a high concentration of phosphates, heavy metal ions, colloidal impurities & non-degradable organic compounds, the water is subjected to tertiary treatment c) Tertiary treatment The process includes a) Treatment with lime for the removal of phosphates as insoluble calcium phosphate b) Treatment with S2- ions for the removal of heavy metal ions as insoluble sulphides c) Treatment with activated charcoal to adsorb remaining organic compounds & ENGINEERING CHEMISTRY DEPARTMENT, S.I.E.T., TUMKUR 145 SHRIDEVI INSTITUTE OF ENGINEERING AND TECHNOLOGY d) Treatment with alum to remove the colloidal impurities not removed in the previous treatments to further reduce the BOD level 8.14 Define Potable water Marks Water that fit for human consumption & meets the stringent microbiological & chemical standards of quality to prevent waterborne diseases & health risks from toxic chemicals is called potable water 8.15 Define Desalination and explain the methods of desalination Marks The process of partial or complete demineralization of highly saline water such as the sea water is referred to desalination Methods of desalination Reverse Osmosis A reverse osmosis unit consists of a membrane, a vessel & a high pressure pump The membranes are generally made up of cellulose acetate or nylon and are usually fabricated in a cylindrical shape Electrodialysis Principle: Passage of an electric current through a solution of salt results in migration of cations towards the cathode & anions towards the anode The use of semi permeable cation or anion exchange membrane in an electrolytic vessel permits the passage of only cations or anions respectively in the solution An electrodialyzer consists of a chamber carrying a series of compartments fitted with closely spaced alternate cation (C) & anion (A) exchange semi permeable membranes between the electrodes An electrodialyzer unit will have 200 to 1000 compartments The feed water is taken in the dialyzer & the electrodes are connected to a source of an electric current ENGINEERING CHEMISTRY DEPARTMENT, S.I.E.T., TUMKUR 146 SHRIDEVI INSTITUTE OF ENGINEERING AND TECHNOLOGY The anions pass through the anion permeable membrane towards the anode However, these ions not pass through the next membrane which is permeable only to cations Similarly the cations moving in the other direction will pass through the cation exchange membrane but not the next These anions & cations collect in the alternate chambers; the water in these is enriched with salt while that in the other compartments is desalinated Micro porous sieves provided near the electrodes prevent the reentry of any deposit, which might have been formed on the electrodes, into the feed water The enriched & desalinated waters are withdrawn separately The former is rejected & the desalinated water is recycled to further reduce the salt content 8.16 What are Hazardous chemicals? Explain the ill effects of Hazardous chemicals Marks Chemicals which are combustible ,Oxidizers, explosives, flammable, pyrophoric, unstable, water reactive, carcinogens, toxicagents, reproductive toxins, irritants, corrosives, hepatotoxins, nephrotoxins, neurotoxins the release of which may substantially endanger the public health, public welfare or the environment are called hazardous chemicals Hazardous chemical Source Ill effects Cadmium Mining wastes, effluents Renal failure,Bone disease called from plating industries itai-itai,high BP,Kidney damage,destruction of RBC Chromium Plating wastes Lead Discharges Carcinogenic from Severe dysfunction ENGINEERING CHEMISTRY DEPARTMENT, S.I.E.T., TUMKUR of 147 SHRIDEVI INSTITUTE OF ENGINEERING AND TECHNOLOGY mining,metallurgical Kidneys,reproductive systems & operations,plumbing, lead lever,impairement of central & acid batteries peripheral nervous systems Mercury Mineral processing operations,organomercury fungicides,discarded batteries,amalgams,toothfi llings Neurological damage including paralysis,depression & irritability,blindness,insnity,chro mosomes breakage & birth defects Arsenic Radioactive wastes Erosion of natural Skin damage,prolems with deposits,runoff from circulatory systems, increased otchards,runoff from glass risk of getting cancer & electronics production wastes Pesticides Agricultural practices Cyanide Exists in water as HCN, 60-90 mg is a fatal dose to living metal cleaning & beings electroplating Headache, dizziness Large quantities may damage central nervous system Objective Questions: 1) The indicator used for the estimation of total hardness of a given water sample by EDTA method is a) Starch b) EBT c) Ferroin d) Methyl orange 2) Temporary hardness of water is caused due to the presence of a) Calcium carbonate b) Calcium chloride c) Magnesium bi carbonate d) None 3) The method used for desalination of water is a) zeolite process b) Lime soda process c) Ion exchange process d) Distillation 4) The indicator used in the determination of chloride content of water sample by Mohr’s method a) Phenolphthalein b) K2Cr2O4 c) Starch d) Ferroin 5) Permanent hardness of water is caused due to the presence of a) Calcium carbonate b) Calcium chloride c) Magnesium bi carbonate d) All ENGINEERING CHEMISTRY DEPARTMENT, S.I.E.T., TUMKUR 148 SHRIDEVI INSTITUTE OF ENGINEERING AND TECHNOLOGY 6) Winkler methods is used to determine a) COD b) BOD c) DO d) Both D & C 7) Which of the following alkalinity is not present in water is a) CO32- and HCO3- b) CO32- and OH- c) OH- only d) HCO3- and OH8) Secondary treatment of sewage involves a) Biological treatment b) Physical treatment C) Chemical treatment d) All 9) In reverse osmosis the solute particle moves a) From High to low concentration b) low to high concentration c) Does not move d) both a & b 10) The ill effect o chromium is a) Headache b) fatal b) Birth defect c) Cancer 11) In alkaline condition, nitrate ion reacts with phenol disulphoneic acid to give a) Yellow colour b) white colour c) green colour d) brouwn colour 12) In SPADNS method of estimating fluoride ion concentration, wavelength used is a) 410 nm b) 500 nm c) 570 nm d) 620 nm 13) Sulphate ion is precipitated by the addition of a) barium sulphate b) barium nitrate c) barium chloride d) barium phosphate 14) Impurities present in natural water is a) dissolved b) suspended c) organic d) all 15) Indicator used in the determination of alkalinity of water is a) Phenolphthalein b) starch c) EBT d) methyl orange ENGINEERING CHEMISTRY DEPARTMENT, S.I.E.T., TUMKUR 149 SHRIDEVI INSTITUTE OF ENGINEERING AND TECHNOLOGY REVIEW QUESTIONS Discuss the different types of Impurities present in natural with examples What is water analysis? Explain the method of Determining the Total Hardness of Water What is meant by Alkalinity? Explain the method of Determining the Alkalinity in water Explain the method of determining the Chloride content in water Explain the method of determining the Fluoride content in water Explain the method of Determining the Nitrate in water Explain the method of determining the Sulphate content in water by colorimetric method 10.Explain the method of determining sulphate content in water by gravimetric method 11.Define biological oxygen demand 12.Define COD 13.Explain the Sewage Treatment 14.Define Potable water 15.Define Desalination and explain the methods of desalination 16.What are Hazardous chemicals? Explain the ill effects of Hazardous chemicals ENGINEERING CHEMISTRY DEPARTMENT, S.I.E.T., TUMKUR 150 SHRIDEVI INSTITUTE OF ENGINEERING AND TECHNOLOGY I/II Semester B.E Degree Examination, Dec.06/Jan.07 Common to all Branches Engineering Chemistry Time: hrs Max Marks: 100 Note: Answer any five full questions, choosing at Least two questions from each Part A and Part B Part A a Distinguish between gross and net calorific value of a fuel (04 Marks) b What is meant by cracking of petroleum? Explain fluidized bed catalytic cracking (07 Marks) c On burning 0.96 grams of a solid fuel in Bomb calorimeter, the temperature of 3,500 grams of water increased by 2.7°C Water equivalent of calorimeter and latent heat of steam are 385 grams and 587 cals/gram respectively If the fuel contains 5% H2, calculate its gross and net calorific values (06 Marks) d Write a note on power alcohol (03 Marks) a Define electrode potential and derive Nernst equation for electrode Potential (05 Marks) b What are the advantages of secondary reference electrodes? Explain the construction and working of Ag/AgCl electrode (06 Marks) c What are electrochemical cells? Distinguish primary cells from secondary cells with examples (05 Marks) d What are concentration cells? Calculate cell potential of the following cell at 298 k Ag /Ag+ (0.001 M)// Ag+ (0.50 M) / Ag What will be cell potential, when the concentration of silver ions in the above cell is changed from 0.OO1M to 0.0005 M, at same temperature? (04 Marks) a How does a fuel cell differ from battery? Explain the construction ENGINEERING CHEMISTRY DEPARTMENT, S.I.E.T., TUMKUR 151 SHRIDEVI INSTITUTE OF ENGINEERING AND TECHNOLOGY and working of Nickel — metal hydride battery (08 Marks) b Explain the construction, working and application of H fuel cell, with cell reaction (06 Marks) c Give the classification of batteries with examples (06 Marks) a Explain stress corrosion with examples (04 Marks) b What are corrosion inhibitors? Explain how corrosion is controlled by using anodic and cathodic inhibitors? (07 Marks) c Write a brief note on the effect of following factors on the rate of corrosion i) Nature of metal ii) Hydrogen — over voltage iii) Relative areas of anode and cathode (09 Marks) PART B a What is electroplating? Give the technological importance of metal finishing (04 Marks) b Explain the following factors influencing the nature of deposit: i) Complexing agents ii) Brighteners iii) Levellers and iv) wetting agents (08 Marks) c Discuss the electroless plating of copper on PCB (04 Marks) d Write a note on over voltage governing the metal finishing(04 Marks) a Explain the following with examples i) Thermotropic liquid crystal and ii) Lyotropic liquid crystal(06 Marks) b What is homologues series? Explain the liquid crystalline behaviour of homologues of MBBA (06 Marks) c Discuss the instrumentation and applications of conductometric estimation (08 Marks) a What are adhesives? Explain the synthesis and applications of epoxy resin (06 Marks) b What are elastomers? Mention the advantages of synthetic elastomers (04 Marks) c Give the synthesis and applications of butyl rubber (04 Marks) d Discuss the mechanism of conductance in Polyacetylene (06 Marks) a What is potable water? Discuss the purification of water by reverse osmosis process (05 Marks) b Explain the method of determining sulphate content in water by gravimetric method (05 Marks) c Explain the determination of dissolved oxygen by Winkler method Give the involved (06 Marks) d Describe the secondary treatment of sewage by activated sludge ENGINEERING CHEMISTRY DEPARTMENT, S.I.E.T., TUMKUR 152 SHRIDEVI INSTITUTE OF ENGINEERING AND TECHNOLOGY process (04 Marks) First Second Semester B.E Degree Examination, July 2007 Common to All Branches Engineering Chemistry Time:3 hrs.] [Max Marks: l00 Note: Answer any FIVE full questions, choosing at least TWO questions from each part PART A a Describe Fischer-Tropsch method of synthesis of petrol b Explain the process of doping of silicon c What is cracking? Explain fluidized catalytic cracking d Discuss the mechanism of knocking (06 Marks) (05 Marks) (05 Marks) (04 Marks) a Explain the origin of single electrode potential Derive Nernst equation for electrode potential (07 Marks) b what are reference electrodes? Mention the limitations of primary reference electrode and advantages of secondary reference electrodes (04 Marks) C Write a note on calomel electrode (04 Marks) d Represent the cell formed by the coupling of two copper electrodes immersed in cupric sulphate solutions Concentration of cupric ions in one electrode system is 100 times more concentrated than the other Write the cell reaction and calculate the potential at 300 K (05 Marks) a Define fuel cell How does it differ from a conventional galvanic cell? (04Marks) b Explain the following fuel cells: i) Molten carbonate ii) Solid polymer electrolyte (06 Marks) c Explain the following battery characteristics: I) Cycle life ii) Shelf life iii) Energy efficiency (06 Marks) d Describe the construction and working of zinc-air battery(03 Marks) ENGINEERING CHEMISTRY DEPARTMENT, S.I.E.T., TUMKUR 153 SHRIDEVI INSTITUTE OF ENGINEERING AND TECHNOLOGY a Define corrosion Explain electrochemical theory of corrosion, taking iron as a example (08 Marks) b Explain differential metal corrosion with suitable example (06 Marks) c What is cathodic protection? Explain corrosion control by sacrificial anode method (06 Marks) PART B a What is electro less plating? Mention its advantages (04 Marks) b Discuss the following factors influencing the nature of deposit: 1) Throwing power ii) pH of the electrolytic bath and iii)Temperature (06 Marks) c Discuss the electroplating of gold and mention its applications (05 Marks) d Explain electrolessplating of copper and its applications (05 Marks) a Distinguish between Thermotropic and Lyotropic liquid crystals with examples (06 Marks) b Explain the working of a liquid crystal in display systems.(06 Marks) c What are the advantages of instrumental methods? (03 Marks) d Explain the estimation of amount of strong acid in a given solution conductmetrically (05 Marks) a Define polymerization Explain solution and suspension polymerization techniques (05 Marks) b Give the synthesis properties and uses of: i) Teflon ii) Butyl rubber (10 Marks) c What are conducting polymers? Give the structure of polyaniline and mention its applications (05 Marks) a Discuss the types of impurities present in natural water (04 Marks) b Explain the determination of hardness of water by complexometeric method (06 Marks) c Explain the electodialysis method of desalination of water.(04 Marks) d.Discuss determination of chloride by Argentometric method (06 Marks) ENGINEERING CHEMISTRY DEPARTMENT, S.I.E.T., TUMKUR 154 SHRIDEVI INSTITUTE OF ENGINEERING AND TECHNOLOGY First/Second Semester B.E Degree Examination, Dec 07 / Jan 08 Engineering Chemistry Time: hrs Max Marks: l0O Note: Answer any five full questions, choosing at least two questions from each part Part A a Describe the Bomb calorimetric method of determination of calorific value of a solid fuel (06 Marks) b What is reforming of petroleum? Give any three reactions involved in reforming (05 Marks) c What is power alcohol? Give its advantages as a fuel (04 Marks) d What is a photo voltaic cell? Explain its working (05 Marks) a What are ion selective electrodes? Explain the measurement of p of a solution using glass electrode (07 Marks) b Explain the origin of single electrode potential (05 Marks) c Describe the construction and working of a calomel electrode (04 Marks) d Calculate the emf of the cell Fe/Fe2+ (0.01 M)// Ag+ (0.1 M)/ Ag at 298 K, if standard electrode potential of Fe and Ag electrodes are — 0.42 V and 0.8 V respectively (04 Marks) a Explain the construction and working of lead acid battery along with the reactions involved during charging and discharging Mention its applications (08 Marks) b Explain the construction, working and applications of Nickel — metalhydride battery (06 Marks) c Explain the construction and working of the hydrogen oxygen fuel cell (06 Marks) ENGINEERING CHEMISTRY DEPARTMENT, S.I.E.T., TUMKUR 155 SHRIDEVI INSTITUTE OF ENGINEERING AND TECHNOLOGY a Explain the differential aeration corrosion with a suitable example (O8 Marks) b How the following factors affect the rate of corrosion? i) Nature of corrosion product ii) Temperature iii) PH (09 Marks) c Write notes on: i) Galvanizing ii Tinning (06 Marks) Part B a What is electroplating? Explain how the following factors influence the nature of electrodeposit: i) Metal ion concentration ii Wetting agents (05 Marks) b Discuss the electro plating of chromium (05 Marks) c Mention the technological importance of metal finishing (05 Marks) d Explain electroless plating of Nickel and its applications (O8 Marks) a Discuss the instrumentation and applications of colorimetric estimation (08Marks) b What are liquid crystals? Explain the molecular ordering in the following liquid crystal phases: i) Nematic crystal phase ii) Chiral Nematic phase iii) Smectic phase (08 Marks) c Distinguish between thermotropic and lyotrophic liquid crystals with examples (04 Marks) a What are polymers? Explain the free radical mechanism of addition polymerization, taking ethylene as an example (06 Marks) b What is glass transition temperature? Mention its significance Discuss any two factors affecting glass transition temperature (06 Marks) c Explain the manufacture of the following polymers and mention their uses: i) Phenol-formaldehyde ii) Polymethyl methacrylate (08 Marks) a Discuss the different types of impurities present in natural water with examples (04 Marks) b Write a note on reverse osmosis (05 Marks) c Explain the method of determining sulphate content in water by gravimetric method (06 Marks) ENGINEERING CHEMISTRY DEPARTMENT, S.I.E.T., TUMKUR 156 SHRIDEVI INSTITUTE OF ENGINEERING AND TECHNOLOGY d Calculate the COD of the effluent sample, when 25 cm of the effluent requires 8.3 c of 0.001 M K for complete oxidation (05 Marks) First and Second Semester B.E Degree Examination, June/July 08 Engineering Chemistry Time: hrs Max Marks: 100 Note: Answer any FIVE full questions, choosing at least two questions from each part Part-A a Describe the experimental determination of calorific value of a solid the using Bomb calorimeter (06 Marks) b What is synthetic petrol? Describe the Bergius method of synthesis of petrol (05 Marks) c Write a note on reforming of petrol (04 Marks) d Explain construction and working of silicon photovoltaic cell (05 Marks) a What are reference electrodes? Explain the construction and working of alomel electrode (08 Marks) 2+ b Calculate the standard electrode potential of Cu /Cu if its electrode potential at 25° C is O.296V when [ is 0.015 M) (03 Marks) c What are ion-selective electrodes? Explain the measurement of pH of a solution using glass electrode (07 Marks) d Derive Nearns’t equation on electrode potential (08 Marks) a Explain the following battery characteristics: i) Energy efficiency ii) Current capacity iii) Cycle life (06 Marks) b Describe the construction and working of Lead — acid battery (08 Marks) c Describe the construction and working of H —02 fuel cell (06 Marks) a Discuss the effect of following on the rate of corrosion (08 Marks) ENGINEERING CHEMISTRY DEPARTMENT, S.I.E.T., TUMKUR 157 SHRIDEVI INSTITUTE OF ENGINEERING AND TECHNOLOGY I) Nature of the metal; ii) Nature of the corrosion product; iii) pH iv) area effect b Explain differential aeration corrosion with suitable example (06 Marks) c What is cathodic protection? How a metal is cathodically protected by sacrificial anode method (06 Marks) Part – B a Define polarization, decomposition potential and over voltage Mention their significance with reference to electrode position (08 Marks) b How the following affect the nature of electroplating? i) Current density ii) temperature iii) pH iv) organic additives (08 Marks) c What is electro less plating? Mention any two advantages (04 Marks) a What are liquid crystals? Distinguish between thermotropic and lyotropic liquid crystals with examples (06 Marks) b Explain the working of liquid crystals in display systems (06 Marks) c What are the advantages of conductometric titrations over conventional titrations? (03 Marks) d Explain the determination of concentration of an unknown solution by colorimetric method (05 Marks) a Define polymerization Explain different types of polymerization processes with suitable examples (05 Marks) b Give synthesis and uses of the following polymers i) Teflon ii)Neoprene (06 Marks) c Write a note on compounding of resins (04 Marks) d Write preparation, properties and uses of epoxy resins (05 Marks) a Explain temporary and permanent hardness of water (04 Marks) b Define B.O.D and C.O.D and mention various steps involved in sewage treatment (04 Marks) c Describe the argentometric method of estimation of chloride ENGINEERING CHEMISTRY DEPARTMENT, S.I.E.T., TUMKUR 158 SHRIDEVI INSTITUTE OF ENGINEERING AND TECHNOLOGY content of a water sample (04 Marks) d What is potable water? Describe the electrodialysis process of desalination of water (08 Marks) ENGINEERING CHEMISTRY DEPARTMENT, S.I.E.T., TUMKUR 159 [...]... Fischer- tropsch process of preparation of synthetic petrol -is used as raw material a) CO+H2 b) CO2+H2 c) CO+H2O d) CO2+H2O ENGINEERING CHEMISTRY DEPARTMENT, S.I.E.T., TUMKUR 28 SHRIDEVI INSTITUTE OF ENGINEERING AND TECHNOLOGY REVIEW QUESTIONS 1 Define a fuel Explain the classification of fuels with examples 2 Define calorific Value Explain the types of calorific value 3 Mention the SI units of calorific... Explain the production of semiconductor grade silicon 18 Explain the Doping of Silicon? ENGINEERING CHEMISTRY DEPARTMENT, S.I.E.T., TUMKUR 29 SHRIDEVI INSTITUTE OF ENGINEERING AND TECHNOLOGY U N IT – II ELECTRO CHEMICAL ENERGY SYSTEMS ELECTRODE POTENTIAL AND CELLS 2.1 What is an electrochemical cell Explain the classification with examples 5 Marks An electrochemical cell is a device, which is used... combined gas law P1 V1 P2 V2 = T1 T2 2 3 101990 N/m x 0.02 m 101325 N/m2 x V = 293 K 273 K V=0.0188 m3 iii) Calorific value, Q=Heat absorbed by cold water Volume of gas ENGINEERING CHEMISTRY DEPARTMENT, S.I.E.T., TUMKUR 12 SHRIDEVI INSTITUTE OF ENGINEERING AND TECHNOLOGY =348/0.0188 = 18510 k J/m3 iv) Net Q: Water condensed during combustion = 7.5cm3 = 7.5 gram Latent heat of steam at 288 K = 2.454 kJ/g Therefore... Fluidized bed catalytic cracking method The catalyst such as alumina or zeolyte is finely powered and mixed with steam and it is pumped to cracking chamber The feedstock ENGINEERING CHEMISTRY DEPARTMENT, S.I.E.T., TUMKUR 13 SHRIDEVI INSTITUTE OF ENGINEERING AND TECHNOLOGY (gas oil, heavy oil) is preheated to 5000C and forced into the cracking chamber along with the catalyst by a steam blast where a floating... Straight chain hydrocarbons undergo cyclisation producing cyclic hydrocarbons which have higher octane number Ex CH3 – CH2 – CH2 – CH2 – CH2-CH3 n- Hexane Cyclo hexane ENGINEERING CHEMISTRY DEPARTMENT, S.I.E.T., TUMKUR 14 SHRIDEVI INSTITUTE OF ENGINEERING AND TECHNOLOGY 3) Cyclisation and dehydrogenation: Straight chain hydrocarbons undergo cyclisation to form cyclic compounds, which further undergoes dehydrogenation... piston causing a rattling sound which is known as knocking The reactions of normal and explosive combustion of fuel can be given as follows taking ethane as an example ENGINEERING CHEMISTRY DEPARTMENT, S.I.E.T., TUMKUR 15 SHRIDEVI INSTITUTE OF ENGINEERING AND TECHNOLOGY 1.9 Define octane number 2 Marks Octane number is defined as the percentage of isooctane present in a standard mixture of isooctane and... antiknocking agent other than lead, is known as unleaded petrol Ex: MTBE is used, as an antiknocking agent in place of TEL or TML and the petrol is known as unleaded petrol ENGINEERING CHEMISTRY DEPARTMENT, S.I.E.T., TUMKUR 16 SHRIDEVI INSTITUTE OF ENGINEERING AND TECHNOLOGY 1.12 Explain working and principle of Catalytic converter Principle: Use of catalytic converter in the internal combustion engines of automobiles... Bergius Process? 6 Marks Coal is considered as black diamond because of its high utility value The principal elements present in coal are carbon and hydrogen It is ENGINEERING CHEMISTRY DEPARTMENT, S.I.E.T., TUMKUR 17 SHRIDEVI INSTITUTE OF ENGINEERING AND TECHNOLOGY therefore coal can be converted into liquid hydrocarbons from which much demand and needed petrol can be obtained The synthetic petrol can... synthesis gas (CO + 2H2) c) Hydrogenation of carbon monoxide: the Synthesis gas (CO + 2H2) is compressed to 5-10 atm pressure and admitted into a catalytic reactor ENGINEERING CHEMISTRY DEPARTMENT, S.I.E.T., TUMKUR 18 SHRIDEVI INSTITUTE OF ENGINEERING AND TECHNOLOGY containing the catalyst (mixture of cobalt (100 parts), thoria (5 parts) and magnesia (8 parts)) The reactor is heated to about 2500C Hydrogenation,... ethanol in alcohol increases the oxygen content of the fuels and promotes more and complete combustion of hydrocarbons in gasoline It reduces carbon monoxide emission ENGINEERING CHEMISTRY DEPARTMENT, S.I.E.T., TUMKUR 19 SHRIDEVI INSTITUTE OF ENGINEERING AND TECHNOLOGY 1.15 Bio diesel: Biodiesel refers to a vegetable oil- or animal fat-based diesel fuel consisting of long-chain alkyl (methyl, propyl or ... Electrodialysis Hours Text Books A text book of Engineering Chemistry P.C Jain and Monica Jain Dhanpatrai Publications, New Delhi Chemistry In Engineering and Technology ( Vol &2) J.C Kuriacose... Environmental Chemistry Stanley E Manahan , Lewis Publishers Polymer Science V.R Gowariker , Wiley Eastern Ltd ENGINEERING CHEMISTRY DEPARTMENT, S.I.E.T., TUMKUR SHRIDEVI INSTITUTE OF ENGINEERING. .. CO2+H2 c) CO+H2O d) CO2+H2O ENGINEERING CHEMISTRY DEPARTMENT, S.I.E.T., TUMKUR 28 SHRIDEVI INSTITUTE OF ENGINEERING AND TECHNOLOGY REVIEW QUESTIONS Define a fuel Explain the classification of fuels