Engineering Chemistry - Dec 2014
First Year Engineering (Set A) (Semester 1)
TOTAL MARKS: 100
TOTAL TIME: 3 HOURS (1) Question 1 is compulsory.
(2) Attempt any four from the remaining questions.
(3) Assume data wherever required.
(4) Figures to the right indicate full marks.
Solve any one question from Q1 & Q1 (e)
1 (a) Why does magnesium bicarbonate require double amount of lime for softening ?(2 marks) 1 (b) If silica is present in water, what harmful effects it can Cause?(2 marks) 1 (c) Explain the function of calgon and sodium aluminate in water treatment.(3 marks) 1 (d) Discuss zeolite method of water softening with its limitation.(7 marks) 1 (e) A sample of water has been found to contain the following in ppm: Ca(HCO3)2=10.5, Mg(HCO3)2=12.5, CaSO4=7.5, CaCI2=8.2, MgSO4=2.6. Calculate the temporary and permanent hardness in degree French. Calculate lime and soda for 1000 liters of water.(14 marks)
Solve any one question from Q2 & Q2 (e)
2 (a) Differentiate coal from coke.(2 marks)
2 (b) Give significance of ultimate analysis of coal(2 marks)
2 (c) What are octane number and cetane number?(3 marks)
2 (d) The percentage composition by weight of a coal sample was found to be as under: C=81%, H=5%, O=8.5%, S=1%, N=1% and 3.5% ash.
i) Calculate the minimum amount of O 2 and air required for complete combustion of 1kg of this coal.
ii) Percentage composition by weight of the dry products of combustion.(7 marks) 2 (e) What is cracking? Discuss moving bed catalytic cracking with its advantages.(14 marks)
Solve any one question from Q3 & Q3 (e)
3 (a) Give two examples of each, lubricating oils, greases and solid lubricants.(2 marks) 3 (b) Why anti-oxidants are added to lubricants? Give examples of it also.(2 marks) 3 (c) What are the constitutional compounds of Portland cement?(3 marks) 3 (d) Discuss important properties of refractories.(7 marks) 3 (e) An oil sample under test has a Saybolt universal viscosity same as that of standard Gulf oil (low viscosity standard) and Pennsylvanian oil (high viscosity index standard) at 210°F. Their Saybolt universal viscosities at 100°F are 61, 758 and 420 seconds respectively. Calculate viscosity index of the sample oil.(14 marks)
Solve any one question from Q4 & Q4 (e)
4 (a) Why natural rubber needs vulcanization?(2 marks)
4 (b) What are the monomer of butyl rubber? What would be its
4 (c) Differentiate thermoplastic resin from thermosetting resin.(3 marks)
4 (d) Give preparation, properties and uses of any two of the
iii. PMMA(7 marks) 4 (e) Give preparation, properties and uses of any two of the Following:
i. Urea-Formaldehyde resin
ii. Melamine-Formaldehyde resin
iii. Epoxy resin(14 marks) 5 (a) In which region of electromagnetic radiation, do we observe NMR and vibration spectroscopy?(2 marks) 5 (b) Define chromophore and auxochrome.(2 marks) 5 (c) Write a short note on gas chromatography.(3 marks) 5 (d) A water sample is alkaline to both phenolphthalein and methyl orange. 200ml of water sample on titration with N/25 HCl required 5ml of the acid to phenolphthalein end point. When a few drops of methyl orange are added to the same solution and titration was further continued the yellow colour of the solution just turned pink after the addition of another 12ml of acid. Calculate the type and extent of alkalinity present in the water sample(7 marks) 5 (e) Discuss briefly the chemical reactions and methods used for analysis of D.O. parameters in water.(14 marks)