Slacking of lime is affected by
Keeping it exposed to air
Immersing the lime in water
Crushing the lime lumps
None of these
Correct Answer :
B. Immersing the lime in water
Related Questions
Assertion A : Normally turpentine oil is recommended as thinner for indoor painting. Reason R : Turpentine oil is costlier than other thinners. Select your answer according to the coding system given below:
Both A and R is true and R is the correct explanation of A
Both A and R is true but R is not the correct explanation of A
A is true but R is false
A is false but R is true
Good quality cement contains higher percentage of
Tri-calcium silicate
Di-calcium silicate
Tri-calcium aluminate
Tetra calcium alumino ferrite
Pick up the correct statement from the following:
The heating of a material to redness in contact with air, is known as calcination
The property of lime by which it sets or hardens in damp places having no free circulation of air is called setting
The product that remains after calcination of limestone, is called lime
All the above
Percentage content of silica in window glass, is
40 to 45
50 to 55
60 to 65
70 to 75
The frog of the brick in a brick masonry is generally kept on
Bottom face
Top face
Shorter side
Longer side
Which of the following stone is best suited for construction of piers and abutments of a railway bridge?
Granite
Sand stone
Lime stone
Quartzite
The pressure acting on the stones in stone masonry construction should be
Along the direction of bedding planes
At 45° to the direction of bedding planes
At 60° to the direction of bedding planes
Perpendicular to the direction of bedding planes
Which of the following is the purest form of iron?
Cast iron
Wrought iron
Mild steel
High carbon steel
The main function of alumina in brick earth is
To impart plasticity
To make the brick durable
To prevent shrinkage
To make the brick impermeable
Bulking of sand is caused due to
Surface moisture
Air voids
Viscosity
Clay contents
Le-Chatelier's device is used for determining the
Setting time of cement
Soundness of cement
Tensile strength of cement
Compressive strength of cement
Granite mainly composed of quartz and feldspar particles, is obtained from
Sedimentary rocks
Metamorphic rocks
Igneous rocks
All the above
Which of the following cements is suitable for use in massive concrete structures such as large dams?
Ordinary Portland cement
Low heat cement
Rapid hardening cement
Sulphate resisting cement
Which of the following is a rock?
Quartz
Mica
Gypsum
None of the above
The operation of removal of impurities or clay adhering to iron ores, is known as
Dressing
Calcination
Roasting
Smelting
Chlorite, a green colour mineral is mainly derived from the decomposition of
Augite
Biotite
Hornblende
All of these
For one cubic metre of brick masonry, number of bricks required, is
400
425
450
500
Stones used for ornamental work must be
Soft
Hard
Light
Heavy
Red short iron cracks when bent due to the presence of
Sulphur
Carbon
Phosphorus
Silicon
Pick up the correct statement from the following:
For thin structures subjected to wetting and drying, the water cement ratio should be 0.45
For mass concrete structures subjected to wetting and drying, the water ratio should be 0.55
For thin structures which remain continuously under water, the watercement ratio by weight should be 0.55
All the above
Cross cut saw is used for
Cutting soft stones
Cutting hard stones
Cutting large blocks of stones
Dressing stones
Gypsum consists of
H₂S and CO₂
CaSO4 and H₂O
Lime and H₂O
CO₂ and calcium
Wrought iron contains carbon upto
0.25 %
1.0 %
1.5 %
2 %
Second class bricks
Are of dark brown colour
Produce a metallic sound when struck
Are well burnt
Are under burnt
Pick up the correct statement from the following:
In basic Bessemer process, the steel heats the converter
In open-hearth process, the furnace heats the steel
In Siemens process, the impurities of pig iron are oxidised by the oxygen of the ore
All the above
Plywood has the advantage of
Greater tensile strength in longer direction
Greater tensile strength in shorter direction
Same tensile strength in all directions
None of the above
Duco paints are
Plastic paints
Cellulose paints
Emulsion paints
Oil paints
Bituminous fells are used for
Covering A.C. sheets
Covering sloping roofs
D.P.C.
None to these
Plastic bitumen is generally used for
Road pavements
Expansion joints
Crack fillings
None to these
Which one of the following is used for preparing porcelain?
Clay
Feldspar
Quartz
All of these