_______________ is used as a flux in the smelting of copper ore like chalcopyrite ?
(A) Coke breeze
(B) Lime powder
(C) Silica/quartz
(D) Dolomite
Poly Vinyl Chloride (P.V.C.) is a ______________ material ?
(A) Thermosetting
(B) Thermoplastic
(C) Fibrous
(D) Chemically active
Temperature during hydrogenation of oil should not be more than 200°C, otherwise it will result in______________________?
(A) Pyrolysis of oil
(B) Sintering of porous catalyst
(C) Hydrogen embrittlement
(D) All A,
Rancidity of the fatty oil can be reduced by its__________________?
(A) Decoloration
(B) Hydrogenation
(C) Oxidation
(D) Purification
Thermosetting plastic materials____________________?
(A) Can be repeatedly melted
(B) Is useful for melt casting
(C) Cannot be melted after forming
(D) Is useful for spinning
Digestion of wood-base materials (for manufacture of pulp) is done to __________________?
(A) Remove lignin
(B) Produce long fibres
(C) Prevent deterioration on storage
(D) None of these
Antibiotic____________________?
(A) Inhibits/destroys the growth of microorganisms
(B) Is used as a pain reliever
(C) Is an antimalarial
(D) Is an anaesthetic
______________ is a thermosetting plastic?
(A) Polyvinyl chloride
(B) Polythene
(C) Bakelite
(D) Teflon
Linde process of gas liquefaction employs__________________?
(A) Exchange of heat with colder stream
(B) Adiabatic expansion through a throttle valve (Joule-Thomson expansion)
(C) Adiabatic expansion against a piston or in a turbine
(D) Merely compressing the gas beyond its critical pressure