Set 1
24005
B. Tech. I Semester
Examination-2021
Engineering Chemistry
CH-101-F
Time: 3 Hrs MM: 100
Note: Attempt five questions in total selecting at least one question from each
section. Q 1 is compulsory. All questions carry equal marks.
1. Answer the following:
(i) What is lather factor?
(ii) Name three substances used for sterilisation of water.
(iii) Why is Bakelite used in electrical appliances and why is Teflon highly
chemical resistant?
(iv) What is a promoter? Can it alone act as catalyst?
(v) How does the entropy of the system changes when; (a) a solid is melted,
(b) a gas is liquefied, (c) H2O is frozen?
(vi) Why additives are used in lubricants?
(vii) Calculate the number of component, number of phases and degree of
freedom for the following equilibria: Solid carbon in equilibrium with
gaseous CO, CO2 and O2 at 373 K.
(viii) What is the difference between Scale and sludges?
(ix) What do you mean by reverse osmosis?
(x) Define and give an example of condensation polymerisation. (2 x 10)
Section A
2. With the help of a phase diagram, discuss salient features of Pb-Ag system.
How can the thermal analysis be employed for determining phase diagram? (12, 8)
3 (a) What are enzymes? How do they behave as catalysts? 8
(b) Explain the following with examples:
(i) Homogeneous catalysis
(ii) Heterogeneous catalysis
(iii) Shape selective catalysts
(iv) Negative catalysts 12
Section B
4(a) Write short notes on:
(i) Ion Exchange Process
(ii) Boiler Corrosion
(iii) Mixed bed deionization 5×3
(b) Discuss a method of determination of hardness of water. 5
5 (a) Discuss Lime-Soda treatment method of softening of water. 8
(b) Write a short note on alkalinity of water and method of determination of it. 8
(c) Calculate temporary hardness and total hardness of a sample of water containing:
Ca (HCO3)2 = 16.2 mg /L ; Mg (HCO3)2 = 7.3 mg/L ; CaSO4 =13.6 mg/L ;
MgCl2 = 9.5 mg/ L. 4
Section C
6. (a). What do you mean by Electroplating? Describe two methods of electroplating. 8
(b) Discuss the mechanism of Rusting of iron. 8
(c) Write short note on microbiological corrosion. 4
7. (a) What are lubricants? Discuss the classification of lubricants. 8
(b) Write short note on the following
1. Synthetic Lubricants
2. Viscosity and viscosity index
3. Properties of Lubricants 12
Section D
8 (a) What are thermoplastics and thermosets? Discuss technical applications of Teflon, UF
and SBR. (4, 6)
(b) Differentiate between addition, condensation and co-ordination polymerization. 6
(c) Write a short note on Biodegradable polymers. 4
9 (a) State Lambert and Beer’s Law and discuss the basic principle of spectroscopy. (2, 4)
(b) Write down the principle and working of DTA. How is it different from DSC? 12
(c) Why spectroscopic methods are better than the classical methods? 2
Set 2
24005
B. Tech. I Semester
Examination-2021
Engineering Chemistry
CH-101-F
Time: 3 Hrs MM: 100
Note: Attempt five questions in total selecting at least one question from each
section. Q 1 is compulsory. All questions carry equal marks.
1. Answer the following:
(i) What are solid lubricants? Give examples.
(ii) Why is Teflon highly chemical resistant?
(iii) What is autocatalysis?
(iv)Name three substances used for sterilisation of water.
(v) A solution of thickness 2 cm. transmits 40% incident light. Calculate the
concentration of the solution, given Ɛ = 6000 dm3 mol-1 cm-1.
(xi) What is the basic principle of thermal methods of analysis?
(xii) Write the reactions for the preparation of Teflon.
(xiii) Why spectroscopic methods are better than the classical methods?
(xiv) Define stress corrosion.
(xv) What do you mean by congruent and incongruent melting point? (2 x 10)
Section A
2(a) Define phase rule. Explain phase diagram of a one component system. 10
(b) Discuss phase diagram of Na2SO4-H2O system. 10
3(a) Write an explanatory note on enzymatic catalysis. 10
(b) Explain the role of promoters and poisoners in catalysis. 10
Section B
4 (a) What is the principle of EDTA titration? How hardness is determined by this method?
What is the role of buffer in this method? (8, 5, 2)
(b) 100 ml of a raw water sample on titration with H 2SO4 required 12.4 ml of the acid to
phenolphthalein end point and 15.2 ml of the acid to methyl orange end point. Determine the
type and extent of alkalinity present in the water sample. 5
5 (a) Write short notes on:
(i) Ion Exchange Process
(ii) Caustic Embrittlement
(iii) Break Point Chlorination (5×3)
(b) Explain composition, properties and methods of prevention of scale and sludges. 5
Section C
6 (a) What do you mean by Electroplating? Describe two methods of electroplating. 8
(b) Write short note on the following:
(i) Cloud point and pour point
(ii) Consistency and drop point of greases
(iii) Biodegradable lubricants 12
7 (a) Why additives are used in lubricants? Give some examples. 6
(b) Explain the mechanism of Dry corrosion. 6
(c) Write short note on the following:
(i) Pitting Corrosion
(ii) Microbiological Corrosion 8
Section D
8 (a) Explain the principle & application of IR spectroscopy. What is the importance of finger
print region in this technique? 10
(b) Write an explanatory note on absorption and emission spectroscopy. 8
(c) A solution of thickness 2 cm. transmits 40% incident light. Calculate the concentration
of the solution, given Ɛ = 6000 dm3 mol-1 cm-1. 2
9(a) What are synthetic rubbers? Discuss preparation, properties and technical applications
of GR-N. 8
(b) Write short note on the following:
(i) Differences of thermoplasts and thermosets
(ii) Resins and Plastics
(iii) Polymeric composites 12
Set 1
24005
B. Tech. I Semester
Examination-2021
Engineering Chemistry
CH-101-F
Time: 3 Hrs MM: 100
Note: Attempt five questions in total selecting at least one question from each
section. Q 1 is compulsory. All questions carry equal marks.
1. Answer the following:
(i) Why spectroscopic methods are better than the classical methods?
(ii) Name three substances used for sterilisation of water.
(iii) Why is Bakelite used in electrical appliances and why is Teflon highly
chemical resistant?
(iv) What is a promoter? Can it alone act as catalyst?
(v) How does the entropy of the system changes when; (a) a solid is melted,
(b) a gas is liquefied, (c) H2O is frozen?
(vi) Why additives are used in lubricants?
(vii) Calculate the number of component, number of phases and degree of
freedom for the following equilibria: Solid carbon in equilibrium with
gaseous CO, CO2 and O2 at 373 K.
(viii) Why is Teflon highly chemical resistant?
(ix) A solution of thickness 4 cm. transmits 60% incident light. Calculate the
concentration of the solution, given Ɛ = 6000 dm3 mol-1 cm-1.
(x) Define stress corrosion (2 x 10)
Section A
2(a) Explain the differences among melting, eutectic and triple point. Give example. 5
(b) Justify the statement, “The eutectic is a mixture and not a compound” 5
(c) In the phase diagram of water, the melting curve is almost a straight line, and it slopes slightly
backwards. Does an increase in pressure increase or decrease the melting point of ice? 5
(d) What are the number of phases in closed beaker partially filled with (a) benzene and water, (b)
acetone and water? 3
(e) If there is no triple point in the diagram of one-component system, then what inference do you
draw? 2
3(a) How many phases are present in the following systems? (a)Finely ground mixture of graphite,
sulphur and sodium chloride.? (b) An iceberg floating on clear sea water in presence of clean air. 4
(b) What are enzymes? How do they behave as catalysts? 8
(c) Explain Shape selective catalysis and Negative catalysis with examples. 4
(d) Discuss the effect of pressure on : (i) transition temperature of rhombic sulphur, and
(ii) melting point of ice. 4
Section B
4(a) What are the requirements of boiler feed water? 4
(b) How is hardness of water expressed? Prove that mg/L is the same as hardness in ppm of water. 4
(c) How is the exhausted resing regenerated in ion exchange method? 4
(d) Distinguish between softening and demineralisation of water. Explain any two methods of
demineralization of water. 8
5(a) Why is hard water unsuitable for boilers? 4
(b) Explain caustic embrittlement in boiler. How does it affect the efficiency of boilers and how can it
be avoided? 8
(c) Why does magnesium bicarbonate require double amount of lime for softening? 4
(d) Explain why is the indicator EBT added in estimation of hardness of water by EDTA method? 4
Section C
0
6(a) Though aluminium has high E ox (standard oxidation potential)
Section D
