JNTU Exam Papers – I B.Tech Regular Examinations– Applied Chemistry – May/Jun 2008
1. Distinguish the following:
(a) Hard water and soft water
(b) carbonate and non-carbonate hardness
(c) mg/litre and ppm
(d) Sedimentation and filtration.
2. (a) Discuss the disadvantages of using hard water for various industries.
(b) Explain the factors responsible for the corrosion of a boiler. Discuss the measures for its prevention.
3. (a) Describe how electrochemical properties are used in protecting submerged metals from being corroded.
(b) Explain the corrosion of iron by dilute mineral acids.
4. (a) List the differences between anodic coating and cathodic coating.
(b) How zinc coated on iron prevents corrosion?
(c) Explain sand blasting method of surface preparation?
5. (a) Differentiate between LDPE & HDPE.
(b) What are the drawbacks of raw rubber?
(c) Write the repeating unit for the following:
i. Nylon 6,6
6. (a) Define Refractories and what are the criteria of a good refractory?
(b) Give the classification of refractories with suitable examples.
7. (a) What is meant by blended oils? Explain the functions of various additives added to the lubricants?
(b) What are viscosity & viscosity index of lubricating oil?
8. (a) Discuss the chemical and physical changes that occur during the setting of cement with relevant chemical equetions..
(b) Write a note on decay of cement concrete and its prevention.