In curing cement plasters water is sprinkled from time to time.This helps in
keeping it cool
developing interlocking needle like crystals of hydrated silicates
hydrating sand and gravel mixed with cement
converting sand into silicic acid
When concentrated HNO3 is heated with P2O5, it forms
N2O
NO
NO2
N2O5
Which is not a mineral of aluminium?
Anhydrite
Bauxite
Corundum
Diaspore
The mixture of conc.HCl and HNO3 made 3:1 ratio contains
ClO2
NOCl
NCl3
N2O4
Which of the following is most stable ?
Sn2+
Ge2+
Si2+
Pb2+
For making good quality mirrors, plates of flint glass are used. These are obtained by floating molten glass over a liquid metal which does not solidify before glass. The metal used can be
Tin
Sodium
Magnesium
Mercury
Graphite is a soft, solid lubricant,extremely difficult to melt. The reason for this anamolous behaviour is that, graphite
is an allotropic form of diamond
has molecules of variable molecular masses like polymers
has carbon atoms arranged in large plates of rings of strongly bound carbon atoms with weak inter plate bonds
is a non-crystalline substance.
Which of the following is a component of ruby?
CaCO3
MgCO3
Al2O3
Al(OH)3
In the alumino-thermite process, Al acts as
Flux
Oxidizing agent
Reducing agent
Promoter
H3BO3 is
Monobasic and weak Lewis acid
Monobasic and weak Bronsted acid
Monobasic and strong Lewis acid
Tribasic and weak Bronsted acid
