07a1bs07 Engineering Chemistry

Code No. 07A1BS06

UNIT-3

ENGINEERING CHEMISTRY 1. 2. 3.

4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15.

Write chemical reactions taking place using stress corrosion of brass. illustrate the reaction involved in differential aeration corrosion with reference to the iron materials How iron corrodes in neutral or alkaline solutions ?what are the laws of oxide film growth during corrosion How material selection and design can prevent carrion? Which protective coatings can be used for corrosion prevention and explain the mechanism of differential aeration . give two examples where differential aeration effect are seen Explain the type of corrosion occurring in the following cases a)bolt and nut made from different metals are in contact with each other b)deposition of small particles of dust on iron surfaces What is meant by “passivity”? comment on use of aluminium in place of cathodic protection of iron from rusting How can galvanic corrosion be controlled ? how is steel protected cathodically? Give example Explain sacrificial anodic protection method of controlling corrosion.write in brief on impressed current method of cathodic protection Explain differential aeration corrosion. What are the factors which effect the rate of corrosion How do the following factors influence the rate of corrosion a) polorisation b)electrode potential Explain the following methods of corrosion control a)cathodic protection b) galvanization What is corrosion, describe the mechanism of electro chemical corrosion by : a)hydrogen evolution b)oxygen absorbsion State and explain pilling bed worth rule, Discuss in detail about chemical corrosion What is pitting corrosion ? describe the mechanism of electro chemical corrosion . discuss the role oxygen in corrosion cells? Describe the various factors affecting the rate of corrosion, define the corrosion ,name the different theories of corrosion, describe galvanic corrosion? Define corrosion . explain losses due to corrosion. Give the classification of corrosion according to environment or surrounding ,distinguish between anodic and cathodic protection

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Code No. 07A1BS06

UNIT-4

ENGINEERING CHEMISTRY 1. What are the ingredients of an oil? state their role, and write two methods of paint application 2. Write spray painting and dipping methods of paint application and write names and functions of thinners and fillers in paints 3. Write short note on “luminous paints” and what is the difference between fluorescent paint and phosphorescent? give one example each for fluorescent pigment and phosphorescent pigment 4. Write note on mechanical methods of surface cleaning and write method of metal surface preparation by sand blasting prior to finishing 5. What is meant by acid pickling and what is its use? how is galvanization of iron particles carried out? 6. Write short note on anodizing and electroplating? What is cementation and how is it done? 7. What is known as metal finishing? Give a brief account of electroplating. and write one method of each galvanizing and tinning 8. Why iron pipe is galvanized? Write two methods of surface preparation? Explain the importance of tinning in corrosion 9. Mention distinguishes between electro plating and electrolous plating and mention their advantages 10. Discuss the role of following factors on the nature of electro deposit: a)current density b) throwing power of plating bath c)pH 11. Explain electro plating as on anti corrosive device? Give an account of nickel plating 12. Explain the term decomposition potential . mention its significance with reference to electro deposition of metals 13. What are the constituents of paints give example .what are their functions 14. What is sand flasting ? what are the different types of corrosion resistant floor finishes? Explain 15. What is the process for chromium plating? Explain its main objectives and uses .explain why chromium plating has nickel undercoat?

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Code No. 07A1BS06

UNIT-5

ENGINEERING CHEMISTRY 1. Distinguish between thermoplastic & thermosetting polymers or resins & discuss with examples the types of polymerization. 2. Define thermoplastic polymers and give two examples,and define the term polymer 3. What is chain polymerization and explain the steps involved and explain the process of step growth polymerization with examples 4. Explain the effect of structure on the properties of a polymer also explain the strength of polymer 5. What is meant by compounding of plastics what are the different constituents of compounding plastics write their uses 6. Write short notes on silicones ,how are they manufactured and write about compounding of rubber 7. What is glass transition temperature discuss the parameters effecting the glass transition temperature. what is its significance 8. Why do all simple organic molecules not produce polymers and why are plastics indispensable in every day life 9. Give reason: a)natural rubber need vulcanization b) pvc is soft whereas bakelites is hard 10. What is meant by reinforced plastics and condensation polymerization 11. What is latex?how is natural rubber isolated from it what is vulcanization? How does it improve the property of natural rubber 12. Write on : 1) free radical polymerization 2)cationic polymerization 3)silicone resins 13. How is crepe rubber obtained from latex? What are the ingredients used in compounding of plastics? Explain their importance 14. Distinguish between nylon-6 and nylon-66 15. How are Teflon and nylon different from one and another? Describe briefly the industrial applications of polymer, write a note on foamed plastics

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