JNTU Exam Papers – I B.Tech Regular Examinations– Engineering Chemistry – May/Jun 2008
1. (a) Why is sterilization of water necessary? Discuss any two methods of sterilisation.
(b) 0.5 g of CaCO3 was dissolved in dil.HCl and diluted to 1000 mL. 50 mL of this solution required 48 mL of EDTA solution for titration. 50 mL of hard water sample required 15 mL of EDTA solution for titration. 50 mL of same water sample on boiling, filtering etc, required 10 mL of EDTA solution. Calculate the different kinds of hardness in ppm.
2. Write short notes on :
(a) Priming and Foaming
(b) Phosphate conditioning
(c) Caustic embrittlement.
3. (a) What is oxidation corrosion and how does it take place? Describe the mechanism of oxidation corrosion.
(b) Describe the various factors influencing the rate of chemical corrosion.
4. (a) Describe the process of sheradizing? Mention its applications?
(b) Distinguish between anodizing and electroplating.
(c) Define Anodizing.
5. (a) How is HDPE is prepared? Give its properties and uses?
(b) Explain the injection moulding process with a neat diagram? Mention its advantages.
6. (a) What is pyrometric cone equivalent? How it is determined for a refractory? What is its significance?
(b) Write a short note on:
ii. Thermal Conductivity
iii. Dimensional Stability.
7. (a) Give the functions of lubricants.
(b) Describe the mechanism of extreme pressure lubrication.
(c) How a viscous lubricant is converted into grease?
8. (a) What do you understand by the term knocking in IC engines? Explain its relationship with chemical constituents of fuels.
(b) A sample of coal contains 60% carbon, 33% Oxygen, 6.0% Hydrogen, 0.5% Sulphur, 0.2% Nitrogen and 0.3% Ash. Calculate GCV and NCV of coal.