Fuels and Combustion

A. Washing fine coal dust (< 0.5 mm size)
B. Washing lump coal (> 80 mm size)
C. Removing ash from the coal based on difference in specific gravity of coal and ash
D. All A., B. and C.

A. Recarbonising steel
B. Making carbon electrodes
C. Blending with highly coking coal to check its swelling which helps in saving coke even walls
from damage and to produce high strength coke
D. All A., B. and C.

A. 5
B. 25
C. 55
D. 75

A. Flue gases
B. Ash content in the fuel
C. Incomplete combustion
D. Unburnt carbon in flue gases

A. Insecticides (e.g. moth balls)
B. Unsaturated polyesters
C. Drug intermediates e.g. β-naphthol
D. All A., B. and C.

A. 2.4
B. 1.75
C. 0.87
D. 11.4

A. Potassium hydroxide
B. Cuprous chloride
C. Alkaline pyrogallol solution
D. None of these

A. Low temperature carbonisation
B. High temperature carbonisation
C. Medium temperature carbonisation
D. Heating the coal in an oven in presence of air

A. Increase
B. Decrease
C. Increase or decrease depending on the fuel type
D. Not change

A. Metallurgical coke
B. Soft coke
C. Very low calorific value coke oven gas
D. No by-products