The main aim behind cooling the digested chip at the bottom portion of the digestor by injecting cold black liquor is to
Avoid mechanical weakening of fibre
Remove lignin by way of crystallisation
Increase the cellulose content
None of these
Correct Answer :
A. Avoid mechanical weakening of fibre
Related Questions
Chrome tanning and vegetable tanning are done for
Light & heavy leather respectively
Heavy & light leather respectively
Both light & heavy leather
Neither light nor heavy leather
Zeolite is used in the
Water treatment
Glass manufacture
Hydrogenation of fatty oil as a catalyst
Development of exposed photographic plate
Good quality of edible salt is obtained from brine by the process of
Solar evaporation
Vacuum evaporation
Freeze drying
Electrolysis
Transparent soaps (e.g. Pears) are
Usually soft soap (made from coconut oil) in which cane sugar & alcohol are added and finally washed with methylated spirit to achieve transparency
Metallic soaps with frothing agent and free Stearic acid to achieve transparency
Metallic soaps with frothing agent from which glycerine has not been recovered
None of these
Phthalic anhydride is used
In making PVC
As plasticisers
In insecticides manufacture
For making nylon-6
Fermentation is adversely affected by the
Presence of air
Absence of air
High concentration
Presence of ammonium salts
Hydrogenation of oil does not
Remove double bonds
Raise its melting point
Improve its resistance to oxidation
None of these
Which of the following is an unsaturated fatty acid?
Lauric acid
Palmitic acid
Stearic acid
Oleic acid
Function of sodium thiosulphate (hypo) in development of photographic film/plate is to
Brighten the faint images
Remove metallic silver
Convert silver chloride to silver
Remove unexposed silver halide
Poly Vinyl Chloride (P.V.C.) is a __________ material.
Thermosetting
Thermoplastic
Fibrous
Chemically active
Thermal pyrolysis of ethylene dichloride produces
Trichloroethylene
Vinyl chloride
Ethanol amine
Ethylene oxide
Coke used for the production of calcium carbide should have
Low ash content
Low ignition temperature
High electrical resistivity
All (A), (B) and (C)
Alcohol percentage in molasses may be around
10
40
70
85
Liquefaction of gases cannot be done by
Exchange of heat with colder stream
Adiabatic expansion through a throttle valve (Joule-Thomson expansion)
Merely compressing it beyond critical pressure
Adiabatic expansion against a piston or in a turbine
Phthalic anhydride is produced by the oxidation of
Naphthalene
Benzene
Toluene
Aniline
Zeigler process
Produces high density polyethylene
Produces low density polyethylene
Uses no catalyst
Employs very high pressure
Cooking liquor in case of sulphite process is
Sodium sulphite and sodium bisulphite
Magnesium sulphite and free SO2 in acid medium
Magnesium sulphate and magnesium bicarbonate
None of these
__________ is a thermosetting plastic.
Polythene
Epoxy polymer
P.V.C.
Polystyrene
Silicone is a/an
Thermoplastic
Inorganic polymer
Monomer
None of these
Thorium is mainly used
For the manufacture of gas mantles
As a fissile fuel in a nuclear reactor
In the manufacture of hydrogen bomb
In the treatment of cancer
Mineral oils (e.g. petroleum oils) are preferred over fatty oils (e.g. mustard oil, ghee, tallow, palm oil, olive oil etc.) as a lubricant due to its
Poor oxidation stability and high gum forming tendency
Greater tendency of decomposition at elevated temperature
Hydrolysis tendency in presence of water
All (A), (B) and (C)
Addition of calcium oxide to water produces
Exothermic heat
Hissing sound
Slaked lime
All (A), (B) & (C)
Iron ore hematite is concentrated using
Electromagnetic separation mainly
Gravity separation
Froth floatation
Roasting
Vinyl chloride (CH2 = CH.Cl) is produced by the thermal pyrolysis of ethylene dichloride at a pressure & temperature of
4 kgf/cm2 & 500°C
10 kgf/cm2 & 1000°C
40 kg/cm2 & 200°C
100 kgf/cm2 & 500°C
Average sulphur content in Indian pyrites is about __________ percent.
15
35
55
70
The chamber process is
Preferred over contact process for producing 98 to 100% H2SO4 and various oleums
Non-catalytic and operates only on pyrites
A batch process for directly producing high strength (98 to 100%) H2SO4
None of these
Temporary hardness of water can be removed by
Addition of alum (a coagulant)
Boiling
Filtration (through gravity sand filter)
Addition of lime
Nylon-6 is manufactured from
Caprolactam
Hexamethylene diamine and adipic acid
Hexamethylene diamine and Maleic anhydride
Hexamethylene diamine and Sebacic acid
Which of the following is the main constituent of the mother liquor produced in salt industry?
Quick lime
Glauber's salt
Salt petre
Bromine
Low temperature carbonisation of coal takes place at __________ °C.
300
1100
700
900