Formula for quick lime, is
CaCO3
Ca(OH)2
CO3CO2
None to these
Correct Answer :
A. CaCO3
Related Questions
The wedging is adopted for quarrying costly stratified rock such as
Laterite
Marble
Limestone
All the above
The ultimate tensile strength of structural mild steel is about
160 N/mm²
260 N/mm²
420 N/mm²
520 N/mm²
For light and ornamental casting, the most unsuitable pig iron, is
Bessemer pig
Grey or foundry pig
White or forge pig
Mottled pig
For melting one tonne of cast iron
700 m3 air is required
20 kg limestone is required
One quintal coke is required
All the above
Specific gravity for most of the building stones lies between
1.5 to 2.0
2.0 to 2.5
2.5 to 3.0
3.0 to 3.5
Seasoning of timber is essential to remove
Knots from timber
Sap from timber
Twisted fibre from timber
Roughness of timber
Pick up the correct statement from the following:
Roasting is not necessary if iron ore is an oxide
Impurities float on the molten iron as slag
The slag contains lime about 45%
All the above
Quick lime (or caustic lime)
Is obtained by the calcination of pure lime stone
Has great affinity to moisture
Is amorphous
All the above
Sandstone is a (i) Sedimentary rock (ii) Aqueous rock (iii) Siliceous rock The correct answer is
Only (i)
Both (i) and (ii)
Both (i) and (iii)
All (i), (ii) and (iii)
Asbestos
Is a natural fibrous mineral substance
Is composed of hydrous silicates of calcium and magnesium (CaSiO3, 3MgSiO3)
Contains iron oxide and alumina
All the above
The most common admixture which is used to accelerate the initial set of concrete is
Gypsum
Calcium chloride
Calcium carbonate
None of the above
Which of the following pairs gives a correct combination of the useful and harmful constituents respectively of a good brick earth?
Lime stone and alumina
Silica and alkalies
Alumina and iron
Alkalies and magnesium
The main constituent which imparts hydraulicity to hydraulic lime is
Calcium oxide
Silica
Clay
Water
The most important constituent of an oil paint, is
Thinner
Vehicle
Pigment
All the above
Spirit varnish generally consists of
Oil, wax and resin
Alcohol, wax and turpentine
Pigment and synthetic resin
Spirit and shellac
Three basic raw materials which are needed in large quantities for production of steel are
Iron ore, coal and sulphur
Iron ore, carbon and sulphur
Iron ore, coal and lime stone
Iron ore, carbon and lime stone
Due to attack of dry rot, the timber
Cracks
Shrinks
Reduces to powder
None of these
Pick up the polymineralic rock from the following:
Quartz sand
Pure gypsum
Magnesite
Granite
Calcination of iron ores is done
To remove moisture
To remove carbonic acid
By roasting in heaps
All the above
Good quality sand is never obtained from
River
Lake
Sea
Gravel powder
With storage, strength of cement
Increases
Decreases
Remains the same
None to these
For preparing porcelains, the clay should be
Sufficiently pure
Of high degree of tenacity
Of good plasticity
All the above
Pick up the plutonic rock from the following:
Granite
Dolerite
Basalt
All the above
The softest rock is
Marble
Diamond
Talc
Quartz
Pick up the correct statement from the following:
Bull's trench kiln a trench excavated in ground
Hoffman's kiln is constructed over ground
Tunnel Kiln is constructed as a tunnel
All the above
Early attainment of strength in rapid hardening cement is mainly due to
Gypsum
Finer grinding
Tri-calcium silicate
Tri-calcium aluminate
For obtaining vinyl chloride acetate, the method used, is
Addition polymerization
Condensation polymerization
Co-polymerization
None of these
For testing compressive strength of cement, the size of cube used is
50 mm
70.6 mm
100 mm
150 mm
Pick up the correct statement from the following:
The substance which consists of one primary chemical, is known as monomer
The polymer consists of thousands of monomers joined together
The polymer molecule is called macro-molecule
All the above
Duco paints are
Plastic paints
Cellulose paints
Emulsion paints
Oil paints