The main ingredient of a good quality brick earth, is
Magnesia
Lime
Silica
Alumina
Correct Answer :
D. Alumina
Related Questions
The thermosetting plastic
Becomes rigid when moulded at suitable pressure and temperature
At 127°C to 177°C permanently set and further application of heat does not soften it
Chars at 343°C
All the above
The variety of pig iron used for the manufacture of steel by Bessemer process, is
Bessemer pig
Grey pig
White forge pig
Mottled pig
Which of the following sedimentary rocks changes into quartzite by metamorphic action?
Sand stone
Lime stone
Shale
Gypsum
Pick up the synthetic resin from the following:
Urea resin
Phenolic resin
Resorcinol resin
All of these
The most important constituent of an oil paint, is
Thinner
Vehicle
Pigment
All the above
Pick up the correct statement from the following:
Blisters in the finished wrought iron, are caused due to the reaction between oxide of iron and carbon
The edges of a finished wrought iron are rough due to red shortage
Pig iron (charcoal) is manufactured from magnetic ore (Fe3O4)
All the above
The proportions of lime and sand in the mortar normally used in brick construction are
1 : 2
1 : 4
1 : 6
1 : 8
Portland cement manufactured from pure white chalk and clay but free from iron-oxide, is known as
Quick setting cement
Rapid hardening cement
White cement
Low heat Portland cement
A stone is rejected if it absorbs water more than
5 %
10 %
15 %
20 %
Mild steel is used for
Structural works in beams, joints and girders
Small sized water pipes
Columns and struts
None of these
Pick up the correct statement from the following:
The free quartz suddenly expands at a temperature lower than 600°C
The lime stone resists fire upto about 800°C and at higher temperature it splits into CaO and CO2
The sand stone with silicates resist a fire in a better way
All the above
Sapwood consists of
Innermost annular rings around the pith
Portion of timber between heartwood and cambium layer
Thin layers below the bark
Thin fibre which extends from the pith outwards and holds the annular rings together
Manganese steels
Are non-magnetic
Possess high electrical resistance
Possess low coefficient of expansion
All the above
Quick setting cement is produced by adding
Less amount of gypsum in very fine powdered form
More amount of gypsum in very fine powdered form
Aluminium sulphate in very fine powdered form
Pozzolana in very fine powdered form
According to ISI, bitumen is classified into
2 grades
4 grades
8 grades
10 grades
Porcelain is used as:
Sanitary wares
Electric insulators
Storage vessels
Reactor chambers
Mastic asphalt is
Acid resisting material
Non-corrosive material
Corrosive material
Heating-resisting material
Advantage of a clamp compared to a kiln for burning bricks is that
It takes less time for burning
It gives more output of first class bricks
It has less initial cost
It is suitable when bricks are required in large numbers
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
The basic purpose of a retarder in concrete is
To increase the initial setting time of cement paste in concrete
To decrease the initial setting time of cement paste in concrete
To render the concrete more water tight
To improve the workability of concrete mix
If water required for 1 bag of cement is 30 litres, the water cement ratio is:
0.40
0.50
0.60
None of these
The operation of removal of impurities or clay adhering to iron ores, is known as
Dressing
Calcination
Roasting
Smelting
Oil varnish generally consists of
Synthetic resin and spirit
Oil, wax and resin
Resin, oil and turpentine
Spirit, oil and wax
Gypsum is a
Mechanically formed sedimentary rock
Igneous rock
Chemically precipitated sedimentary rock
Metamorphic rock
Which of the following represents a metamorphic rock? (i) Slate (ii) Shale (iii) Quartzite The correct answer is
Only (iii)
Both (i) and (iii)
Both (ii) and (iii)
All (i), (ii) and (iii)
For sanitary pipes and chemical stonewares,
Salt glazing is used
Lead glazing is used
Opaque glazing is used
None of these
Pick up the correct statement from the following:
Rust is due to formation of oxides
Cast iron oxidises less
Steel oxidises most
All the above
Bitumen emulsion is
A liquid containing bitumen in suspension
A paint
Used as anti-corrosive paint
All the above
The main constituent which imparts hydraulicity to hydraulic lime is
Calcium oxide
Silica
Clay
Water
The percentage of water for normal consistency, is
5% to 15%
10% to 25%
15% to 25%
20% to 30%