Engineering Chemistry-II-Pune-Winter-2015
B.E. Second Semester All Branches (C.B.S.)
Time: 2 hours
Maximum marks: 50
Notes :
1. Neat diagrams must be drawn wherever necessary.
2. Figures to the right indicate full marks.
1. (a) Discuss the Ion-Exchange method for softening of hard water with the help of reactions involved in removal of ions and regeneration of the exchangers. Draw a neat labelled diagram
and give limitations of the process. [6M]
(b) Define the following terms : [3M]
i) Bathochromic shift
ii) Hypochromic shift
iii) Chromophore.
(c) Explain the conductometric titration curve for the reaction between KC1 and AgNO3. [3M]
OR
2. (a) Explain the potentiometric titration of Fe2+ against Ce4+ giving reactions. Draw the titration curve and give the formulae for calculating emf of the cell at various stages of the titration. [6M]
(b) Give the demerits of the traditional route and merits of the green route of synthesis of polycarbonate. [3M]
(c) 50 ml of water sample required 12.1 ml of N/50 HC1 to reach the phenolphthalein end-point and 18.5 ml of the same acid for the methyl orange end-point. Calculate types and amount of alkalinities present. [3M]
3. (a) Define glass transition temperature. Give its significance and discuss any four factors affecting it. [6M]
(b) Define GCV and NCV. Give the justification of how they are related. [3M]
(c) A coal sample has the following composition : C = 70%, H = 10%, N = 3%, S = 3%, 0 = 2% and ash = 12% If 20% excess air is required for complete combustion, then calculate the amount of air required for complete combustion of 1 kg of coal. [3M]
OR
4. (a) Explain in brief the process of fractional distillation of petroleum with diagram. Give the composition and boiling range of petrol and diesel obtained. [6M]
(b) Give the purpose and examples of the following constituents used during the compounding of plastics : [3M]
i) Fillers
ii) Lubricants
iii) Plasticisers.
(c) Explain solution polymerisation technique. Draw the figure and state the disadvantages of this technique. [3M]
5. (a) Explain the structure of fullerene. Give any two properties and two applications of fullerene. [5M]
(b) Give the preparation reaction and applications of germane and lithium hydride. [4M]
(c) Discuss the properties of hydrogen which make it difficult for storage. [4M]
OR
6. (a) Explain the production of hydrogen by water splitting using solar energy. [6M]
(b) Discuss the different types of carbon nano tubes with respect to their structure. Give any two applications of it. [4M]
(c) Explain the structure of graphite. Give its properties and applications. [4M]
7. (a) Give the Pilling-Bedworth ratio and its significance. Give the oxidation reaction involved and state the type of film formed on the surface in the case of Mg, Cr and Mo. [5M]
(b) Explain the process of galvanising with labelled diagram. Give the applications and limitations of this technique. [4M]
(c) State the different types of corrosion inhibitors with their examples. Discuss in brief their role in corrosion prevention. [4M]
OR
8. (a) Discuss any five factors affecting corrosion. [5M]
(b) Define corrosion. Explain the hydrogen evolution mechanism of wet corrosion. [4M]
(c) What is the principle of cathodic protection ? Discuss any one technique of cathodic protection and give its applications. [4M]