The function of gypsum addition during cement making is to
Increase the density of cement
Decrease the cement setting rate
Both (A) and (B)
Neither (A) nor (B)
Correct Answer :
B. Decrease the cement setting rate
Related Questions
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
Type of glass used in optical work is the __________ glass.
Soda-lime
Fibre
Lead
Borosilicate
Coal tar is used as a
Binding material for coal briquettes
Fuel in rotary kiln
Binder in making carbon electrodes
All (A), (B) and (C)
Sodium carbonate (soda ash) is not used in the manufacture of
Fire extinguishers
Sugar
Baking powder
Detergents
Magnesium and calcium __________ cause temporary hardness of water.
Carbonates
Bicarbonates
Phosphates
Sulphates
High purity nitrogen is used in
Making protective gas (95% N2 + 5% H2) for annealing of cold rolled steel strip coils
Fire fighting purposes
Both (A) & (B)
Neither (A) nor (B)
Fire clay is __________ refractory material.
A basic
An acidic
A neutral
Not a
Separation of fresh water from sea water can be done by the __________ operation.
Osmosis
Reverse osmosis
Absorption
Adsorption
Flux addition during smelting of ore is done to
Remove impurities/gangue
Enhance rate of reaction
Accelerate reduction of ore
Separate slag from metal
Chemical name of 'alum' is
Barium sulphate
Aluminium sulphate
Aluminium chloride
Calcium sulphate
Kopper-Totzek coal gasifier
Can give ammonia synthesis gas (H2 + N2)
Is a moving bed reactor
Cannot use coking coal
Operate at very high pressure
Pure rectified spirit contains about __________ percent alcohol.
45
70
95
99.5
Exothermic neutralisation reaction between caustic soda and dodecylbenzene sulfonic acid produces sodium dodecylbenzene sulphate, which is a/an
Explosive
Soap
Detergent
Analgesic drug
The metallic aluminium is obtained from pure alumina in the presence of fused cryolite by
Electrolysis
Electrolytic reduction
Electrolytic oxidation
None of these
Highly porous refractory bricks are
Less susceptible to chemical attack by molten fluxes and gases etc
Very strong
Having very high thermal conductivity
None of these
Silicone is a/an
Thermoplastic
Inorganic polymer
Monomer
None of these
The process used for the manufacture of ethyl alcohol from molasses is
Distillation
Dehydration
Dehydrogenation
None of these
Gun powder, which is an explosive comprises of charcoal, sulphur and
Glycerine
Salt petre
Nitro glycerine
Dynamite
Nylon-6 is a
Polyamide
Thermosetting resin
Polyester
None of these
Salt is the basic raw material for the manufacture of
Cement
Glass
Potteries
Caustic soda
High magnesia lime is added to hot sugar cane juice (during the manufacture of sugar) to
Flocculate the impurities
Facilitate fast filtration
Both (A) and (B)
Neither (A) nor (B)
Vegetable oils and fats basically differ in their
Density ranges
Physical state
Chemical composition
Chemical properties
Percentage of alcohol in beer may be around __________ percent.
2-8
18-23
27-32
1-4
Pick out the wrong statement.
Hard glass which is used for making laboratory glass wares is a mixture of sodium borosilicate and aluminium borosilicate
Glass is decolorized during its manufacture by adding antimony oxide, manganese dioxide or arsenic oxide
Ordinary glass is represented chemically by Na2O . CaO . 6SiO2
Red color is imparted to glass by addition of arsenic oxide
All enzymes are made of
Fats
Carbohydrates
Proteins
Amino acids
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 sugars is the sweetest?
Glucose
Fructose
Sucrose
Lactose
Synthesis gas is a mixture of
CO and H2
N2 and H2
H2, CH4 and CO
CO2 and H2
Which of the following is an explosive?
Nitro-glycerine
Trinitrotoluene (TNT)
Cellulose nitrate
All (A), (B), and (C)
The main use of activated carbon in water treatment is to control
Bacterial growth
Taste and odour
Turbidity
None of these