VIDYA PRATISHTHAN’S COLLEGE OF ENGINEERING, BARAMATI
QUESTION BANK FOR PRELIM SEMESTER – II
SUBJECT: ENGINEERING CHEMISTRY
(CLASS FE I, II & III 2015 -16)
UNIT- I: WATER TECHNOLOGY
Q1. Describe the Demineralisation process of softening of hard water. What are its advantages over
Zeolite method?
(6)
Q2. How are alkalinities in a water sample determined? State the type of alkalinities. (6)
Q3. Give the difference in sludge and scales in Boiler. Explain any one method of internal treatment
for scales.
(6)
Q4. State the general principle involved in Internal Treatment of Boiler scales. Give any two
Methods of Internal Treatment.
(5)
Q5. State various ill effects of using hard water in boilers. Explain in detail (i) Scale and Sludge
Formation, (ii) Boiler Corrosion.
(6)
Q6. Give the differences in Sludges and Scales boiler. (4)
Q7. What are the causes, disadvantages and preventions of scales and sludges in boilers?
(6)
Q8. Give causes, disadvantages of caustic embrittlement & propose methods to minimize it. (6)
Q9. Give the cause, effects of boiler corrosion and the methods to minimize the corrosion.
(4)
Q10. Give any two chemical methods for treatment of scales during boiler in operation. (4)
Q11. What is meant by „internal treatment‟ of boiler feed water? Explain phosphate conditioning. (4)
Q12. Explain base exchange by
i) Zeolite process
ii) By using synthetic resin with the chemical reactions involved
(6)
Q13. Define scale. What are the bad effects if hard water is used in boilers?
(7)
Q14. Define Anion and Cation Exchanger. Explain demineralization process of hard water. (7)
Q15. What is meant by hard water? What are the causes of hardness? Define alkaline & non- alkaline
hardness of water. (4)
Q16. Explain EDTA method of determining total hardness of water sample along with chemical
reactions involved and structure of metal – EDTA complex.
(6)
Q17. Explain caustic embrittlement & its effect. Suggest the remedies to avoid it. (4) May 2014 (3)
Q18. Explain causes, disadvantages & prevention of (any two)
a) Priming & foaming
b) Scales & sludges
c) Boiler corrosion
d) Caustic embrittlement
(6)
Q19. State the effect of following impurities in water when used as a boiler feed & suggest the
preventive measures (any three).
i) Oil & grease
ii) Dissolved O2 & CO2
iii) CaSO4
iv) Na2CO3
(6)
Q20. Explain base exchange by Zeolite process. Give regeneration reactions.
(6)
Q21. What is demineralization of water? Describe demineralisation by ion exchange process. (6)
Q22. Write the chemical reactions involved in cation & anion exchanger, if water contains,
i) Ca(HCO3)2
ii) MgSO4
iii) Ca(NO3)2
(3)
Engg. Chem QB
1
Q23. What is the internal treatment of boiler feed water? Explain Calgon & colloidal conditioning. (6)
Q24. Explain phosphate conditioning with the help of chemical reactions.
(4)
Q25. Give reason a. Sodium phosphate is preferred for high pressure boilers.
b. Hydrazine is added to boiler feed water.
c. It is essential to remove calcium sulphate before feeding water into the boiler.
d. Inner walls of high pressure boilers are treated with tannin /lignin.
e. In Ion exchange process, water is first passed through cation exchanger bed followed by
anion exchanger bed.
(2 each)
Q26. Name the type of phosphates used for a) Acidic water b) highly alkaline water & c) slightly alkaline
water. Explain with chemical reactions.
Q27. What are the impurities present in water?
(2)
Q28. Explain different types of impurities present in water with examples. (4)
Q29. What is desalination of brackish water? Explain any one method of desalination. (6)
Q30. Write short note on: i) Reverse osmosis. (ii) Electrodialysis.
(6)
Q31. Explain the methods of internal treatment of boiler feed water. (6)
Q32. Explain boiler corrosion and caustic embrittlement as ill effects of using hard water in boilers.
State their causes and preventive measures.
(6)
Q33. Explain formation of scales in boiler, give their disadvantages and methods of removal. (6) Dec13
Q34. Describe Ion Exchange method for softening of hard water (6) May 2014 (Demineralization)
Q35. Define scale and sludge. Give the causes, disadvantages and removal of scale and sludge from
boiler.
(6) Dec 2014
Q36. What are „Zeolites‟. Explain Zeolite process of softening of water. Give regeneration reactions,
advantages and disadvantages of the process.
(6)
Dec 2014
Numerical Bank for Water
Q1) 100 ml water sample requires 4.3 ml of 0.02N HCl upto Phenolphthalein end point. And total
11.9 ml upto Methyl Orange end point. Calculate the type and amount of alkalinity present. (3)
Q2) Find the hardness of water sample from the given data – A zeolite bed gets exhausted on
softening 2400 lit of water and requires 10 lit of 8% NaCl for regeneration.
(3)
Q3. 100 ml of water sample requires 18.5 ml of M/50 disodium EDTA for end point in titration. 100
ml of the same water sample after boiling and filtration, takes 10.7 ml of the disodium EDTA for
end point in titration. Calculate temporary and permanent hardness of the water sample in ppm
CaCO3 equivalent.
(5)
Q4. A zeolite bed gets exhausted on treatment of 2000 litres of a water sample. The exhausted bed
requires 20litres of 12% NaCl solution for regeneration. Calculate the hardness of the water
sample. (5)
Q5. An exhausted Zeolite softener bed was regenerated by passing 50 lit. of NaCl containing
250gm/lit of NaCl .Hard water sample of hardness 400 ppm CaCO3 equivalent was softened by
using the bed. Calculate quantity of hard water which can be softened by this bed. (3)
Q6. 100 ml water sample requires 4 ml of N/50 H2SO4 for neutralization to Phenolphthalein end
point. Another 16 ml the same acid was needed for further titration to Methyl Orange end point.
Determine the type and amount of alkalinities. (3)
Engg. Chem QB
2
Q7. 50 ml standard water containing 2.5 mg CaCO3 per ml consumed 15 ml EDTA. 25 ml water
sample required 20 ml EDTA and 25 ml boiled sample water required 13 ml EDTA solution.
Calculate total, temporary and permanent hardness. (5)
Q8. 100 ml sample water on titration with N/50 HCl required 17.5 ml for phenolphthalein end point.
When methyl orange was added to the same, pink colour developed. Describe the type and
amount of alkalinity present in the water sample. (2)
Q9. Find the types and amount of alkalinities in the water sample if 100 ml water sample on titration
with 0.02N H2SO4 gave phenolphthalein end point 8.5ml of the acid and 12.5 ml acid was further
required to methyl orange end point. (4)
Q10. Hardness of 2,500 litres of water was removed completely by zeolite softener. The zeolite had
required 40 litres of 100 gm lit. of NaCl to regenerate. Calculate hardness of water. (4)
Q11. A zeolite bed gets exhausted 3500 litres of water sample. It requires 10 litres of 10%NaCl
solution for regeneration. Find the hardness of water sample. (4)
Q12. 50 ml of an alkaline water sample requires 9.2 ml of N/50 HCl upto phenolpthaline End point
and total 13.1 ml of the acid for complete neutralization. Find the types and amounts of
alkalinities in the water sample. (5)
Q13. A Zeolite bed exhausted by softening 4,000 litres of a water sample requires 10 litres of 15%
NaCl solution for regeneration. Calculate the hardness of the water sample. (3)
Q14. 50 ml standard water containing 1.2 gm CaCO3 per litre required 15ml EDTA solution for the
end point. Whereas 50 ml water sample required 19ml EDTA solution and 50 ml boiled sample
water required 11ml of EDTA solution for the end point. Calculate total, temporary and
permanent hardness of water sample in ppm.
(3)
Q15. 50 ml of water sample requires 12.7 ml of 0.02 M EDTA during titration. Calculate the total
hardness of the water sample.
(4)
Q16. An exhausted Zeolite softener was regenerated by passing 150 litres of sodium chloride solution
having strength 150 gm/litre of NaCl. How many litres of hard water sample having hardness 400
ppm can be softened by using this softener? (4) Dec 13
Q17. A water sample is not alkaline to phenolphthalein. However 100 ml of water sample on titration
with N/50 HCl required 16.9 ml of acid to get methyl orange end point. Identify the type and
determine the extent of alkalinity. (3) May 2014
Q18. A water sample is not alkaline to phenolphthalein indicator. However 100 ml of the same
sample on titration with 0.02 N H2SO4 requires 14.5 ml of acid to obtain end point using methyl
orange. Identify the type of alkalinity and determine its extent. (3) Dec 2014
Q19. 50 ml of water sample requires 18 ml of 0.05 M EDTA during titration. Whereas 50 ml of boiled
water sample required 12.5 ml of same EDTA solution in the titration. Calculate total,
temporary and permanent hardness of water sample.
(3) Dec 2015
UNIT- I: GREEN CHEMISTRY
Q1.
Q2.
Q3.
Q4.
What is green chemistry? Discuss the need of green chemistry. (4)
State in brief goals of green chemistry. (4)
State the principles on which green chemistry is developed.
(6)
Define the term which gives information about „maximum incorporation of the reactants into the
final product.‟ Explain with suitable example.
(4)
Engg. Chem QB
3
Q5.
Q6.
Q7.
Q8.
Discuss any one synthesis which is based on alternative feed stock using green chemistry.
(4)
Discuss the synthesis of polycarbonate by traditional route and compare it with greener route.
(4)
Discuss the synthesis of polycarbonate by greener route and compare it with traditional route.
(4)
Give the alternative or greener process used in the synthesis of indigo dye. State the advantages
of this process.
(4)
Q9. Discuss the synthesis of indigo dye by traditional route and compare it with greener route.
(4)
Q10. Give the synthesis of adipic acid by traditional route and compare it with greener route.
(4)
Q11. Give the synthesis of adipic acid by greener route and compare it with traditional route.
(4)
Q12. Discuss the research efforts made using green chemistry approach in the area of,
a) Alternative feedstock.
b)
Alternative reagents.
(4)
Q13. State the problems in traditional synthesis route and advantages of green route in the
manufacture of adipic acid.
(3)
Q14. Give various industrial applications of green chemistry.
(4)
Q15. Explain any six principals of green chemistry.
(6)
Q16. What are the drawbacks of traditional synthesis of indigo dye? Which is the starting substance in
its green route synthesis? What are the advantages of green route synthesis over traditional? (3)
Q17. What are the drawbacks of traditional synthesis of polycarbonate? Which is the starting substance
in its green route synthesis? What are the advantages of green route synthesis over traditional? (3)
Q18. What are the drawbacks of traditional synthesis of adipic acid? Which is the starting substance in
its green route synthesis? What are the advantages of green route synthesis over traditional?(3)Dec 13
Q19. What are merits of green synthesis and demerits of traditional synthesis of indigo dye? (3) Dec 2014
UNIT- II: ELECTROANALYTICAL TECHNIQUES
Q1. What are the reference electrodes? Describe the construction of calomel electrode.
(4)
Q2. Define electrode potential. Write the half cell reactions taking place on iron, when it is connected
with copper and placed in dilute sulphuric acid solution.
(4)
Q3. Describe construction of indicator electrode i.e. glass electrode and represent the electrode.
Q4. What is e.m.f.? How it is measured potentiometrically?
(4)
+2
+4
Q5. Describe the procedure for titration of Fe / Ce titration using potentiometry. (4)
Q6. How the end point of redox titration is determined using potentiometric titration. Explain with
suitable example.
(6)
Q7. Explain the measurement of pH of a solution using glass electrode.
(4)
Q8. What are buffers? Explain the buffer action?
(4)
Q9. Explain or discuss titration of mixture of acids i.e. H3PO4 and HCl.
(6)
Q10. Explain or discuss titration of mixture of acids i.e. CH3COOH and HCl. (6)
Q11. Define:a) Conductance.
b) Specific conductance.
c) Equivalent conductance.
d) Molar conductance.
(1Each) Dec 2014
Q12. What is cell constant? How it is determined experimentally?
(4)
Q13. State the Kohlrausch‟s law and explain how the mobility of ions effect the conductance of the
electrolyte? (4)
Q14. Explain the titration curves for conductometric titration in case of strong acid – weak base and
weak acid weak base titration.
(6)
Engg. Chem QB
4
Q15. Discuss the applications of conductometric titration for precipitation titration with suitable
example on the basis of titration curve.
(6)
Q16. Explain construction of conductivity cell used in the measurement of conductance of solution.(3)
Q17. How electromagnetic radiations are generated? Give the characteristics of electromagnetic
radiation.
(4)
Q18. Expalin the principle, instrumentation and applications of UV – Visible spectrophotometer. (6)
Q19. Explain electromagnetic spectrum. (3)
Q20. Discuss the principles of spectroscopy.
(3)
Q21. Explain the instrumentation of spectrophotometry with the help of block diagram
(4).
Q22. State and explain Lambert‟s law of absorption.
(3)
Q23. State and explain Beer‟s law of absorption
(3) Dec 2014
Q24. Define the term auxochrome. Explain with suitable example.
(3)
Q25. Define the term chromophore. Explain with suitable example.
(3)
Q26. What is meant by „red‟ (Bathochromic shift)? Why it occurs? Explain with example.
(4)
Q27. Define hypsochromic shift (blue shift). Give reason for blue shift and explain with example. (4)
Q28. Draw schematic block diagram for single beam and double beam spectrophotometry.
(4)
Q29. On progressive dilution specific conductance of an electrolyte decreases but molar conductance
increases. Give reason.
(3)
Q30. Explain the titration curves for conductometric titration in case of strong acid – strong base and
weak acid strong base titration.
(6)
Q31. Discuss the interaction of EMR with molecules having set of discrete energy levels.
(4)
Q32. Explain different types of electronic transitions that occur in the molecule after absorbing UV
radiations.
(4)
Q33. What is meant by hperchromic effect? Explain with example.
(3)
Q34. What is meant by hypochromic effect? Explain with example.
(3)
Q35. State types of intensity shifts and explain each with example.
(4)
Q36. Explain redox titration between Ce (IV) ion and Fe(II) ion solution.
(6)
Q37. Explain different types of Electronic transitions that occur in an organic molecule after absorbing
UV radiations.
(6)
Q38. Explain pH metric titration of mixture of weak acid-strong acid against standard alkali, giving
reactions, procedure, titration curve and calculations.
(6)
Q39. Which are the possible transitions that occur when molecule absorbs UV-Visible radiation?
Which type of electronic transitions will be possible in following molecules?
(i) CH2 = CH – CH2 – CH3
(ii) CH3 – CH2 – OH
(3)
O

(iii) CH3 – C – CH3
(iv) CH3 – CH2 – CH2 – CH2 – CH3
Q40. State the reference electrode and standard electrode used in pH metry, Potentiometry and
Conductometry.
(3)
Q41. Explain the effect of dilution on specific conductance and equivalent conductance.
(3)
Q42. Explain the titration curves for conductometric titration in case of strong acid – weak base
titration.
(3)
Engg. Chem QB
5
Q43. Calculate potential on redox electrode dipped in titration mixture, when 20 ml of 0.1 N Ce 4+
solution from burette is added in 100 ml 0.1 N Fe2+ solution. Standard reduction potentials for
Fe2+  Fe3+ and Ce4+  Ce3+ are 0.75 V and 1.45 V respectively.
(3) Dec 13
Q44. Explain the conductometric titration of KCl against AgNO3 solution from burette. (3) Dec 13
Q45. Explain conductometric titration curve for reaction between weak acid & strong base titration. (3) May14
Q46. Explain different types of electronic transitions occurring in organic molecules on absorption of
UV-Visible radiations. (6) May 2014
Q47. Explain pH metric titration of mixture of weak acid-strong acid against std. Alkali giving chemical
reaction, procedure with titration curve. (6) Dec 2014
UNIT- III: SYNTHETIC ORGANIC POLYMERS
Q1. Give the definitions & give one example each.
[1mark each]
i) Monomer
ii) Polymer
iii) Degree of polymerization (Dp)
iv) Glass Transition temperature.( Tg)
v) Polymerization
vi) Functionality
Q2. Write a note on molecular weight of polymers.
(4)
Q3. Give any one method for averaging molecular weight of polymer. (3)
Q4. What is Glass transition temperature? Explain importance and factors affecting GTT.
(6)
Q5. Classify polymers on the basis of:
a) Polymerization mechanism
(3)
b) Thermal behaviour.
(3)
Q6. Distinguish thermoplastic and thermosetting polymers with suitable example. (3) Dec 2014
Q7. Give the free radical mechanism of chain polymerization of an example.
(5)
Q8. Give preparation properties & uses of, a) Polyethylene & b) Epoxy resin.
(6)
Q9. Explain compounding of plastics with examples.
(5)
Q10. Explain Latex processing of rubber. (4)
Q11. What is Vulcanization of rubber? Give the structural changes taking place on Vulcanization by
using Sulphur.
(6)
Q12. Give the structure, properties and drawbacks of natural rubber.
(4)
Q13. Give the step growth mechanism of chain polymerization of an example.
(4)
Q14. Give preparation reaction, properties & uses of SBR.
(3) May 14
Q15. Compare the following.
(a) Chain and step polymerization.
(3)
(b) Natural rubber & vulcanized rubber.
(3)
Q16. Write a note on (a) Polymer composites & (b) liquid-crystalline polymers.
(6)
Q17. Write a note on (a) Conducting Polymer & (b) thermally stable polymer
(6)
Q18. Write a short note on biodegradable polymers.
(5)
Q19. Distinguish between LDPE and HDPE. (any 4 points)
(3) May 2014
Q20. Explain bulk & solution polymerization techniques with advantages, disadvantages & uses. (6)
Q21. Explain solution and suspension polymerization techniques.
(6)
Q22. Explain Emulsion polymerization techniques.
(3)
Q23. What are engineering thermoplastics? Give advantages of engineering thermoplastics.
(4)
Q24. Give structure, properties and applications of polycarbonate.
(4)
Engg. Chem QB
6
Q25. What are biodegradable polymers? Explain the features of the polymer that undergo
biodegradation . Give applications of biodegradable polymers.
(6)
Q26. Give structure, properties and applications of poly (hydroxyl butyrate-Hydroxyvalarate). (3)
Q27. What are intrinsic and extrinsic conducting polymers? Explain with examples.
(4)
Q28. Give structure and mechanism of conduction of polyacetylene.
(4)
Q29. What are electroluminescent polymers? Explain use of electroluminescent polymers in LED. (4)
Q30. Give structure, properties and applications of polyphenylene vinylene.
(3)
Q31. Give structure, properties and applications of Kevlar.
(3)
Q32. What is fibre reinforced plastic? Explain any one type of fibre reinforced plastic with
composition, advantages and applications. (4)
Q33. Write a note on (a) Electroluminescent polymers (b) Engineering thermoplastics
(6)
Q34. Explain Bulk and Emulsion polymerization techniques.
(6)
Q35. Explain Solution and Suspension polymerization techniques.
(6)
Q36. Explain Kevlar and FRP with respect to their properties and applications. (6)
Q37. Define Vulcanization of rubber? Explain Vulcanization of natural rubber along with chemical
reactions involved. Compare natural rubber with vulcanized rubber w.r.t. their properties.
(6)
Q38. Explain free radical mechanism for addition polymerization w.r.t. monomer as vinyl chloride and
initiator as acetyl peroxide.
(3)
Q39. Explain free radical mechanism for addition polymerization w.r.t. monomer as vinyl alcohol and
initiator as acetyl peroxide.
(3)
Q40. Explain free radical mechanism for addition polymerization w.r.t. monomer as styrene and
initiator as benzoyl peroxide.
(3) Dec 13
Q41. Give structural change on vulcanization of natural rubber molecules with sulphur. How does it
affects the strength?
(3) Dec 13
Q42. State the purpose of compounding polymers with plasticizers and fillers.
(3) Dec13
Q43. Define biodegradation of polymers. State favourable structure of polymer for degradation.
Write structure of biopol (PHBV).
(3) Dec 13
Q44. Define addition Polymerization. Explain free radical reaction mechanism with suitable example.
(6) May 2014
Q45. Give preparation reaction, properties & uses of following polymers.
a) LDPE
b) SBR.
(6) Dec 2014
Q43. What is biodegradable polymer? Give the structure of PHBV and its applications? (3) Dec 2014
UNIT- IV: FUELS & COMBUSTION
Q1.
Q2.
Q3.
Q4.
Define fuel. Classify fuels on the basis of their physical state with examples.
(4)
Define: Gross Calorific Value and Net Calorific Value.
(2)
NCV is having lower value than GCV. Explain.
(4)
What is general principle of all calorimeters? Explain working of Bomb Calorimeter with diagram.
(7)
Q5. Explain how Boy‟s gas calorimeter is used to measure calorific value of gaseous fuels. (7)
Q6. Explain the principle & method for determining C.V. of highly volatile fuel or gaseous fuel. (7)
Q7. The following results were obtained in a Boy‟s calorimeter experiment:
(5)
3
The volume of gas burned at NTP
= 0.097m
The weight of water required for cooling = 31.5 Kg
Engg. Chem QB 7
Weight of steam condensed
= 0.028 Kg
Temperature of inlet water
= 26.5 0 C
Temperature of outlet water
= 37.2 0 C
Determine the higher and lower CV of the fuel per cubic meter. The latent heat of steam =580
cal/Kg.
Q8. We can find out only gross calorific value by calorimeters. Explain.
(3)
Q9. State & explain different corrections in determination of GCV using Bomb calorimeter & write the
corrected formula.
(4/5)
Q10. Classify coal. Describe its types with C%, C.V., texture & uses.
(4/5)
Q11. A Bomb calorimeter was used to determine the calorific value of a coal sample containing 4.6% of
hydrogen. Following results were obtained(5)
Amount of coal sample
= 1.06g
Mass of water
= 2.6 Kg
Water equivalent of apparatus = 0.876 Kg
Temperature rise of water
= 3.65 0 C
Latent heat of steam
= 2450 KJ/Kg
Find out the net calorific value in KJ/Kg.
Q12. Define Gross/Higher calorific value and justify the relationship between GCV & NCV of the fuel,
if fuel contains H % of hydrogen.
(3)
Q13. Explain knocking in petrol engine. Define octane number and explain effect of chemical structure
of hydrocarbons present in petrol on knocking.
(6)
Q14. A gas used in internal combustion engine contains, H2 = 45%; CH4 = 35%; CO = 15% & N2 = 5%
by volume. Find the minimum volume of air required per m3 gas for its complete combustion. (3)
Q15. Explain proximate analysis of coal with its significance.
(6)
Q16. What is proximate analysis? Mention the principle involved in the analysis of each of the
constituents with its formula.
(6) May 14
Q17. What is ultimate analysis? Mention principle involved in the analysis of each element. How
theoretical calorific value is determined by this analysis.
(6/7)
Q18. Describe Kjeldahl‟s method of estimating % nitrogen in coal
(4)
Q19. Explain significance of blank & back titration in Kjeldahl‟s method for estimation of N.
(4)
Q20. How % of C & % H is determined in coal.
(4)
Q21. How % of S in coal is determined from washings of Bomb Calorimeter / Eschka mixture
(4)
Q22. State & explain the analysis of coal to decide the rank / type of coal / stage of coalification.
(4)
Q23. Explain advantages and Limitations of Biodiesel.
(3)
0
Q24. 1.18g of coal sample was heated in silica crucible in an electric oven at 110 C for 1hr. The residue
weighed 1.14g. The crucible was ignited to constant weight of 0.087g. In another experiment 1.16g of
sample was heated in silica crucible covered with vented lid at 950 0C for 7 mins. After cooling the
residue weighed 0.76g. Calculate percent fixed carbon and GCV using Goutel formula (G = 117). (6)
Q25. What is natural gas? Give its uses.
(4)
Q26. What is refining of petroleum? Explain various steps involved in it.
(6)
Q27. Discuss the process to separate the mixture of diesel, gasoline & kerosene?
(4)
Q28. What is Knocking? Explain Octane Number and Cetane Number of fuel.
(7)
Q29. A coal sample was subjected to ultimate analysis & following are the results of different analysis.
Engg. Chem QB
8
i) 0.26g of sample on combustion gave 0.81g CO2 and 0.118g H2O.
ii) 1.3g of sample in a Kjeldahl‟s experiment liberated ammonia that was absorbed in 50 ml 0.1N H2SO4.
The resultant solution required 12ml of 0.1N NaOH solution for complete neutralization.
iii) 3.1 g of sample was analyzed by Eschka method and gave 0.46g BaSO4.
Using Dulong formula, calculate gross calorific value and net calorific value of coal in MJ/Kg. (6)
Q30. Give composition, boiling range and uses of any three fractions obtained.
(3)
Q31. Describe the process of distillation of crude petroleum with diagram. Give composition,
boiling range and uses of any three fractions obtained.
(7)
Q32. Write a short note on refining of petroleum.
(6)
Q33. Calculate C, H, N, S % from the following observations for a sample of coal:
i) 2.05 g of the coal is burnt in combustion tube. The increase in weight of anhydrous CaCl2 is
0.55g and increase in weight of KOH tube is 5.75g.
ii) 0.75g of the coal in Kjeldahl‟s experiment released NH3, which is passed in 50 ml 0.12N HCl.
The HCl requires 43ml of 0.12N NaOH to neutralize in back titration.
iii) Washings of Bomb pot when 1.8g of the coal sample in Bomb Calorimeter experiment is
treated with BaCl2 solution to give 0.33 g BaSO4.
(4)
Q34. Distinguish between octane number and Cetane number.
(4)
Q35. Explain: (1) Octane number of petrol
(2) Merits and demerits of power alcohol
(6)
Q36. What is the difference between knocking in petrol engine & diesel engine
(3)
Q37. What is biodiesel? How is it made? Give the general chemical reaction involved
(4)/(6)
Q38. Give composition properties & applications of any two of the following gaseous fuels:
a) Natural Gas
b) CNG
c) LPG
(6)
Q39. Total quantity of oxygen required for combustion of solid fuels is given by formula,
(2.67C + 8H + S – O), explain.
(4) Dec 13
Q40. What is the difference between complete & incomplete combustion? Give combustion reactions
for butane, ethane, methane, propane, ethylene, propylene, ethanol, acetylene. (Any 4)
(6) Dec 13
Q41. What is power alcohol? Give its preparation with reactions and any two disadvantages. (3) May14
Q42. What is biodiesel? Give its synthesis and advantages.
(3) Dec 2014
Numerical Bank
Q1. One gram of the coal sample was burnt in combustion tube in oxygen. CO2 was absorbed in KOH
and water vapour in CaCl2. The increase in weight of KOH & CaCl2 was 3.157 and 0.504 gm
respectively. Determine the %C and %H in the sample.
(04)
Q2. 0.072 gm of a fuel containing 80% carbon when burnt in a bomb calorimeter, increased
temperature of water from 27.30C to 29.10C. if the calorimeter contains 250 gm of water & its
water equivalent is 150 gm, calculate GCV of the fuel.
(04)
Q3. A petrol sample contains 14% H and 86% C, calculate the quantity of air required for complete
combustion of 1Kg of petrol.
(04)
Q4. Find the % of C and H in coal sample from the following data – 0.20 gm of coal on burning in a
combustion tube in presence of pure oxygen was found to increase in the weight of CaCl 2 tube by
0.08 gm and KOH tube by 0.12 gm.
(04)
Engg. Chem QB
9
Q5. 2.4 gm of coal sample was weighed in a silica crucible. After heating in an electric oven at 110 0C
for one hour, the residue weighed 2.25 gm. The crucible was then covered with vented lid and
strongly heated for exactly 7 minutes at 950 0C. The residue weighed as 1.42 gm. The crucible
was further heated without lid until a constant weight was obtained. The last residue was found to
be 0.22 gm. Calculate the percentage results of the above analysis.
(04)
Q6. Volumetric analysis of producer gas is H2 = 20%, CH4 = 2%, N2 = 50%, CO =22%, CO2 =6%.
Find the volume of air required for complete combustion of 1m3 of the gas. Air contains 21% by
volume of oxygen.
(04)
Q7. Volumetric analysis of Producer gas is: H2 = 20%, CH4 = 2%, CO = 22%, CO2 = 6% & N2= 50%.
Find the volume of air required for complete combustion of 1m3 of gas. (04)
Q8. In Boy‟s gas calorimeter experiment: when 0.1m3 of a fuel gas is burnt during which 25 kg of
water is circulated. Temperature of incoming water and outgoing water is 20 0C & 33 0C
respectively. Weight of steam condensed is 250 gm. Calculate gross and net calorific values, if
heat liberated in condensing water vapours and cooling the condensate is 586 kcal/kg.
(03)
Q9. A sample of coal containing 5% H2 when allowed to undergo combustion in Bomb calorimeter, the
following data were obtained.
Wt of coal burnt = 0.95 gm
Wt of water taken = 700 gm
Water equivalent of bomb calorimeter = 2000 gm
Rise in temperature = 2.48 0C
Cooling correction = 0.02 0C
Fuse wire correction = 10 cal
Acid correction = 60 cal
Calculate Gross and Net calorific value of coal.
(04)
Q10. A gas has following composition by volume: H2 = 20%, CH4 = 6%, CO = 22%, CO2 = 4%, O2 =
4% & N2 = 44%. Find the volume of air actually supplied per m3 of this gas. (04)
Q11. 0.250 gm of coal sample was burnt in stream of oxygen at 1290 0C in a combustion tube. There
was increase of Mg-perchlorate unit by 0.025 gm and that of soda-lime unit by 0.800 gm after
combustion. Find out % C and H of coal sample.
(04)
Q12. The coal containing 5% hydrogen (dry/ moisture free basis) and 10% moisture has gross calorific
value of 33.5 MJ/Kg. Calculate Net calorific value of coal. Latent heat of water vapour is 2.45
MJ/ Kg.
(03)
Q13. A sample of coal was found to have the following composition: C = 75%, H2 = 5.2%, O2 = 12.8%,
S = 1.2%, N2 = 3.7%, Ash = 2.1%. Calculate the minimum amount of air necessary for complete
combustion of 1 kg of coal.
(04)
Q14. A fuel has the following composition by mass. C = 83%, H = 12%, O2 = 3.2%, S = 1% and the
remaining being ash. Calculate theoretical weight of air.
(04)
Q15. 1.2 gm of coal sample was heated in a silica crucible in an electric oven at 105-110 0C for one
hour, the residue weighed 1.16 gm. The residue was ignited at constant weight of 0.09 gm. In
another experiment 1.2 gm of sample was heated in silica crucible covered with lid at 950  20 0C
for 7 min. After cooling the residue weighed 0.8 gm. Calculate percentage of fixed carbon. (04)
Q16. Compute the proximate analysis results: 1.8 g of a coal sample looses 0.270g weight at 110 0C.
1.5 g of the same coal sample looses 0.36 g weight at 925 0C and 2.2 g of the coal sample leaves
0.28 g of ash.
(04)
Engg. Chem QB 10
Q17. A gaseous fuel contains H2 = 45%, CH4= 30%, N2 = 3%, CO= 6%, C2H4 = 2%, C2H6 =5%, & H2O
vapour = 4%. Calculate the volume of air required for complete combustion of 1m3 of the gas. (4)
Q18. A gaseous fuel contains H2 = 50%, CH4 = 30%, N2 = 2%, CO = 7%, C2H4 = 3%, C2H6 = 5%, H2O
vapour = 3%. Calculate the volume of air required for complete combustion of 1m3 of the gas. (4)
Q19. A coal sample was subjected to ultimate analysis; following are the results of different analysis:
(1) 0.24 g of sample on combustion gave 0.792 g of CO2 and 0.0216 g of H2O.
(2) 1.4 g of sample in a Kjeldahl‟s experiment liberated ammonia which was absorbed in 50 ml
N/10 H2SO4. The resultant solution required 10 ml of N/10 NaOH solution for complete
neutralization.
(3) 3.2 g of sample was analysed by Eschka method and gave 0.233 g BaSO4.
Using Dulong formula, calculate gross and net calorific value of the coal in MJ/Kg. (7/6)
Q20. Calculate C, H, N, S % from the following observations for a sample of coal:
(1) 2.05 g of the coal is burnt in combustion tube. The increase in weight of anhydrous CaCl2 is
0.55 gm and increase in weight of KOH tube is 5.75 gm.
(2) 0.75 gm of the coal in a Kjeldahl‟s experiment released ammonia which is passed in 50 ml
0.12N HCl. The HCl requires 41 ml of 0.12N NaOH to neutralise in back titration.
(3) Washings of Bomb pot when 1.8 gm of the coal sample in Bomb calorimeter experiment is
treated with BaCl2 solution to give 0.31gm BaSO4.
(04)
Q21. A producer gas used as a fuel has following volumetric composition: H2=28%, CO=12%,
CH4=2%, CO2=16%, N2= 42%. Find the volume of air required for complete combustion of 1 m3
of the gas. Air contains 21% by volume of oxygen.
(04)
Q22. 2.5 g of air-dried coal sample was taken in a silica crucible after heating it in an electric oven at
105-110 0C for 1hour, the residue weighed 2.395 g. The residue was then ignited at 700-750 0C to
a constant weight of 0.252 g.
In another experiment 1g of the same sample was heated in a silica crucible covered with a vented
lid at a temperature 950  20 0C for 7 min. After cooling the weight of residue was found to be
0.635g. Calculate % of fixed carbon.
(06)
Q23. The ultimate analysis of a fuel sample is as C = 87.6%, H = 9.8% and S = 2.6%.
(1) Find theoretical O2 requirement.
(2) Then find theoretical air requirement.
(04)
Q24. A coal sample containing 62.4% C, 4.1% H, 6.9% O, 1.2% N, 0.8% S, 15.1% moisture and 9.7%
ash was burnt in such a way that dry fuel gas contained 12.9% CO2, 0.2% CO, 6.1% O2 and 80.8%
N2. Calculate:
i)
The weight of air theoretically required per Kg of coal.
ii) The weight of dry flue gas obtained per Kg of fuel.
iii) The weight of air actually used.
(04)
Q25. A sample of coal was analysed as follows:
(04)
Exactly 2.5 g was weighed into a silica crucible. After heating for one hour at 110 0C, the
residue weighed 2.415 g. The crucible next was covered with a vented lid and strongly heated
for exactly 7 min at 950  20 0C. The residue weighed 1.528g. The crucible was then heated
without the cover, until a constant weight was obtained. The last residue was found to be
0.245g. Calculate the percentage results of above analysis.
Q26. 1.2 gm of coal sample was heated in a silica crucible in an electric oven at 105-110 0C for one
hour, the residue weighed 1.16 g. The crucible was ignited to constant weight of 0.09 g.
In
another experiment 1.2 g of sample was heated in silica crucible covered with vented lid at 950 0C
Engg. Chem QB 11
for 7 min. After cooling the residue weighed 0.8 g. Calculate percentage of fixed carbon and
GCV using Goutel formula. (G = 116).
(06)
Q27. 1.6 g of coal sample in Kjeldahl‟s experiment liberated ammonia which was absorbed in 50ml
0.05N Sulphuric acid. The resultant solution required 14 ml of 0.1N NaOH for complete
neutralization of H2SO4 in back titration. The reading for blank titration was 25 ml. Find percent
of N in coal.
(03)
Q28. Volumetric analysis of producer gas used as fuel is as: H2 =20%, CO =22%, N2 =50%, CH4=2%,
CO2 = 10%. Air contains 21% by volume of O2. Find air required for complete combustion of 1
m3 of the gas.
Q29. A gaseous fuel contains: H2 = 50%, O= 7%, CH4= 30%, C2H4 = 3%, C2 H6 = 5%, N2 = 2% &
H2O vap = 3%. Calculate the volume of air required for complete combustion of 1m3 of the gas.(4)
Q30. A coal containing 62.5% C, 4.3% H, 6.4% O, 1.3% N, 0.9% S, 15.1% moisture & 9.5% ash was
burnt. Calculate the weight of air theoretically required per Kg of coal.
(3)
Q31. Calculate the amount of air (20% excess) required for complete combustion of 1kg wood if it
contains 55% C, 8% H, 5% O and remaining non-combustible part.
(3) Dec 13
Q32. A coal sample contains C: 80%, H: 10%, S: 2.5%, N: 4% and remaining is ash. Calculate the
theoretical quantity of oxygen and air required for complete combustion of 1 kg of given coal
sample.
(3) May 2014
Q33. A gaseous fuel used in internal combustion engine contains: H2 = 30%, CH4 = 45%, CO = 20%,
N2 = 5% by volume. Find the minimum quantity (volume) of air required for complete
combustion of 1m3 of the gaseous fuel. (4) Dec 2014
UNIT- V: CHEMISTRY OF HYDROGEN & CARBON
Q1.
Q2.
Q3.
Q4.
Q5.
Q6.
Q7.
Q8.
Q9.
Describe hydrogen element. What are the names of isotopes of hydrogen?
(4)
What are the isotopes of hydrogen? Give any two applications of hydrogen.
(4)
Describe the importance of isotopes of hydrogen.
(4)
What is electrolysis of water? Explain the industrial process involved in it.
(4)
Explain production of hydrogen by water splitting using solar energy.
(4)
Describe the use of sodium alanate for H2 storage.
(4)
Describe the storage of hydrogen in the form of carbon material with two examples.
(4)
Account for difficulties faced in the storage and transportation of hydrogen.
(4) May 2014
What are binary compounds of hydrogen? Describe applications of any one binary compound of
hydrogen.
(4)
Q10. Describe methane with laboratory and industrial scale preparation and its applications. (4)
Q11. Describe silane with one laboratory and one industrial scale preparation and its applications. (4)
Q12. Explain how Germane can be prepared.
(4)
Q13. What are the types of molecular hydrides? Explain uses of any one molecular hydride. (4)
Q14. Describe ammonia with respect to the types of molecular hydride, laboratory scale preparation
and applications.
(4)
Q15. Explain how saline hydrides are formed. Give preparation and applications of any one saline
hydride.
(4)
Q16. Give applications of hydrogen in various industries.
(4)
Q17. Give an account of H2 as a future fuel.
(4)
Q18. Describe the characteristics of carbon with reference to its position in group 14 in Periodic table.
Engg. Chem QB 12
Q19. Explain the isotopes of carbon with their applications.
(4) May 2014
Q20. Explain the terms: i) Catenation (ii) Carbon dating.
(5)
Q21. Explain structural features and applications of diamond and graphite.
(5) May 2014
Q22. Discuss potential applications of Carbon Nanotubes.
(4)
Q23. Classify allotropes of carbon on the basis of type of hybridization involved. Give applications of
any three allotropes.
(5)
Q24. Give structure, occurrence and applications of diamond.
(4)
Q25. Give structure, occurrence and applications of graphite.
(4)
Q26. What is intercalation? Explain oxidative & reductive intercalation of graphite with example. (4)
Q27. Explain basic structure and applications of graphene.
(5)
Q28. Explain preparation and structure of activated carbon and carbon black.
(4)
Q29. Explain any two partially crystalline allotrope of carbon with structure and applications. (4)
Q30. Explain intercalation of graphite with one example.
(4)
Q31. Explain basic structure, properties and applications of Fullerenes OR . Carbon nano-tubes. (4)
Q32. Explain structure of fullerenes and its conductivity. Give applications of fullerenes.
(5)
Q33. Explain production of hydrogen by Steam reforming of natural gas and coke.
(4)
Q34. Explain the structure of Fullerene. How does it influence its properties and applications?
(5)
Q35. Describe the use of sodium alanate for hydrogen storage.
(4)
Q36. Explain the storage of hydrogen in compressed and liquefied form. Explain difficulties in the said
storage systems.
(4)
Q37. Explain the isotopes of carbon and hydrogen.
(5) Dec 13
Q38. Explain the steam reforming of methane to obtain hydrogen gas.
(4)
Q39. What are the types of CNT with respect to their structure? Give their applications. (4) Dec 2014
Q40. Explain chemical storage method of hydrogen gas in the form of alanates and metal hydrides. (5)
Dec 2014
Q41. Explain preparation and structure of activated carbon and carbon black.
(4)
Q42. What are carbon nanotubes? Explain their types in detail.
(4) Dec 13
Q43. Give industrial methods of manufacturing of hydrogen gas.
(5) Dec 13
Q44. Give preparation reactions of saline hydrides.
(3) Dec 13
Q45. Give preparation reactions of silane.
(4) Dec 13
Q46. Explain manufacturing of hydrogen gas by steam reforming of (i) methane and (ii) coke. (4)
May 14/ Dec 2014
Q47. Explain the structural features of Fullerene with diagram and give its applications. C60 (4) May 14
Q48. What are different types of hydrides? Give preparation reaction of Germane, Silane and lithium
hydride.
(4) May 14
Q49. Explain the structural, properties and applications of fullerene (5) Dec 2014
Q50. Explain the structure and properties of graphite.
(4) Dec 2014
Q51. Give the isotopes of hydrogen with their applications and write the properties of hydrogen which
makes it more difficult to store and transport.
(5) Dec 2014
UNIT- VI: CORROSION
Q1. Define corrosion. Explain corrosion due to following gases.
i) Oxygen
ii) Chlorine iii) Sulphur dioxide iv) Oxides of nitrogen.
[7]
Engg. Chem QB 13
Q2. “Anodic metallic coatings provide better protection to metal than cathodic ones.” Comment. [4]
Q3. Explain different factors affecting corrosion.
[7]
Q4. Why steel pipe connected to copper tank gets corroded? Name and explain type of corrosion. [4]
Q5. Account for cathodic protection methods with respect to principle, method and applications. [7]
Q6. Define corrosion. Explain galvanic and differential aeration Corrosion.
[7]
Q7. Explain the mechanism of wet corrosion.
[6]
Q8. Explain cathodic protection for corrosion control.
[6]
Q9. Define term corrosion. Explain galvanic corrosion with the help of Galvanic series.
[7]
Q10. What is meant by atmospheric corrosion? Explain giving different chemical reactions.
[6]
Q11. Explain different non-metallic coatings for protection against corrosion.
[4]
Q12. Explain corrosion in Zn-coated steel and tin coated steel. Which is more protective? Why? [6]
Q13. Distinguish between: (a)
Anodic coatings and cathodic coatings.
[4] May 14
(b)
Electrochemical series and galvanic series.
[4]
Q14. Explain the hydrogen evolution & oxygen absorption mechanism of electrochemical corrosion. [5]
May / Dec14
Q15. Give note on different forms of corrosion.
[4]
Q16. Explain “impurity in metal” and relative “anodic-cathodic areas” as factor in corrosion.
[4]
Q17. Explain why,
i) Area of anode should be larger.
ii) Metal should be free from impurity.
iii) Contact of dissimilar metals should be avoided.
[6]
Q18. Explain: i) Zn is easily attacked by conc. sulphuric acid but copper does not react.
ii) When exposed to atmosphere, Na is completely corroded but Al remains protected. [6]
Q19. Compare: Galvanizing and Tinning
[4]
Q20. Give the Pourbaix diagram and state the uses of the diagram for a metal.
[6]
Q21. Explain anodic protection of metals for corrosion control with advantages.
[4]
Q22. How the metals are coated by hot dipping methods? Give the applications of galvanizing and
tinning.
[6]
Q23. Describe electroplating and its applications.
[4]
Q24. Give notes on:
a) chemical conversion
b) metallic coatings
[6]
Q25. How are anodized and chemical oxide coatings applied on metal.
[4]
Q26. Explain dry corrosion of Ag, Al, Mo, Na, Zn, Pt, Cr, Fe.(any four)
[4]
Q27. Iron corrodes faster than Al, even though iron is placed below Al in the electrochemical series. Why? [4]
Q28. What is principle of Cathodic protection? Discuss the various types of cathodic protection. [7]
Q29. What is oxidation corrosion? Give general mechanism of oxidation corrosion
[4]
Q30. Compare the rate of oxidation corrosion of following metals – Fe, Na, Mo, Au, Ag, Al, Ni, Cu (any 4)[4]
Q31. What is Pilling Bedworth rule? How the ratio affects the rate of corrosion
[4]
Q32. Explain the dry corrosion by hydrogen.
[4]
Q33. Give reason
(3 - 4 marks each)
i)
Wire mesh corrodes faster at the joints.
ii) A pure metal rod half immersed vertically in water start corroding at the bottom.
iii) A steel screw in brass plate corrodes.
iv) Iron corrodes under drop of salt solution.
v) Rusting of iron is quicker in saline water than in ordinary water.
Engg. Chem QB 14
vi) Copper equipments should not posses a small steel bolt.
vii) Bolt and nut made of same metal is preferred in practice.
viii) In a structure, two dissimilar metals should not come in contact with each other.
ix) Part of nail inside wood undergoes corrosion easily.
x) Deposition of extraneous matter on metal surface for a long period is undesirable.
xi) Nickel plated steel articles should be free from pores and pin holes.
Q34. Copper metal does not undergo much corrosion like iron in moist atmosphere. Give reason.
[4]
Q35. Discuss various factors affecting the rate of corrosion based on nature of metal.
[5]
Q36. Discuss various factors affecting the rate of corrosion considering nature of environment.
[5]
Q37. How do the following factors influences the rate of corrosion.
a) electrode potential
b) Hydrogen over voltage
[4]
Q38. Why anodic coatings are preferred than cathodic coatings on metals
[4]
Q39. Give the Pourbaix diagram for Iron water system and give its significance.
[6]
Q40. Describe any two methods of applying metallic coating
[6]
Q41. Explain surface preparation/surface treatment for applying protective coatings on the
metal surface.
[4]
Q42. What are the objectives & applications of electroplating on metal
[4]
Q43. Explain different types of surface conversion coating.
[4]
Q44. When coating is ruptured, iron is protected in galvanized sheet but not in tin coated sheet.
Explain.
[4]
Q45. Why moderate current density is employed during electroplating.
[4]
Q46. Why anodizing is best suited for aluminium.
[4]
Q47. Explain Blacodizing.
[6]
Q48. Write a note on surface conversion coating.
[4]
Q49. What is powder coating? Explain any one method of powder coating. Give applications of
powder coating.
[5]
Q50. Suggest suitable method for protecting following metallic structure
i) Underground pipeline
ii) Open water box cooler
iii) Ship hull
iv) Food can
v) Paper pins/screws/nut bolts
[5]
Q51. How does the nature of environment influences the rate of corrosion? Explain any four factors
with examples.
[4]
Q52. Discuss various steps involved in powder coating.
[4]
Q53. How is steel galvanized? Explain the process with the help of a flow diagram. [6] / [4] May 14
Q54. Give conditions under which the wet corrosion occurs. Explain the mechanism of wet
corrosion by hydrogen evolution with suitable example.
[4]
Q55. Explain corrosion control using proper designing and material selection method.
[4]
Q56. What is oxidation corrosion? Give general mechanism of oxidation corrosion. Compare oxidation
corrosion which occurs in Na metal, Cu metal and Molybdenum (Mo) metal.
[5] Dec 13
Q57. What are different types of metallic coatings? Which one is preferred? Why?
[3] Dec13
Q58. Account on „nature of oxide films‟ on metal surface and its effect on further corrosion. [4] Dec 13
Q59. What is Pilling Bedworth ratio? Give four types of oxide films formed on the surface of metal with
suitable example
[4] May 14
Q60. What is principle of Cathodic protection? Explain it with any one method. [4] May 14 /Dec 2014
Engg. Chem QB 15
Q61. Discuss factors affecting rate of corrosion, two each, for nature of metal and nature of
environment.
[4] May 14
Q62. Define corrosion and explain effect of following factors on rate of corrosion
i) Purity of metal
ii) Relative area of anode and cathode
[5] Dec 2014
Q63. State the types of oxide film formed on the surface of following metals with reactions.
1) Na
2) Al
3) Au
4) Mo
[4] Dec 14
Q64. What is cathodic coating? Explain tinning with neat labelled diagram to protect metal from
corrosion.
[4] Dec 14
Q65. Define electroplating. Explain electroplating process with neat labelled diagram and applications.
[4] Dec 14
********************************* BEST
OF LUCK
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Engg. Chem QB 16