24.

25.

2

ات

27.

28.

OR

(a) Write the preparation and important properties of silicone rubber.
(b) Write the sol- gel method for the synthesis of nanomaterials. (5+5)

(a) What are greases? Write a brief note on their classification.
(b)The temperature of 1000g of water was increased from 26.5°C to 29.2°C on burning 0.808
of a solid fuel in a bomb calorimeter. Water equivalent of calorimeter and latent heat of steam
are 385 g and 587 cal/g respectively. If fuel contains 0.7% hydrogen calculate its gross and net
calorific value. (6+4)

OR

.(a)Calculate the net and gross calorific value of a coal sample having following

composition:C=82%, H=8%, O=5%, N=1.4% and ash=3.6 %.

(b) Define the properties of a liquid lubricant which are useful for their evaluation under the
following conditions (i) fire hazards (ii) very low temperature.

(c)What is biodiesel? List its environmental advantages. (4+3+3)

(a) Give the theory of EDTA method for estimating the hardness of water.

(0) 2.88 of CaCO; was dissolved in 1101 and the solution diluted to one litre. 100 mL of this

solution required 28 mL of EDTA solution, while 100 ml of the hard water required 35 mL of

the same EDTA solution. On the otherhand 100 mL of the boiled sample water when titrated

against EDTA required 10 mL of EDTA solution. Calculate the temporary and permanent

hardness of water? (4+6)
OR

(a) With the help of a neat diagram outline the reverse osmosis process.

(b)A sample of water is found to contain 48.6 mg/L Ca(HCO3), 43.8 mg/L കവും,

24.0 mg/L MgSO, , 27.2 mg/L CaSO, and 16.8 mg/L NaHCO3. Calculate the carbonate and

non-carbonate hardness of water. (5 +5)
(6x10=60 marks)