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.
Carbogen is
mixture of O2 + 5 - 10% CO2.
used by pneumonia patient for respiration
used by victims of CO poisoning for respiration
All of the above
When concentrated HNO3 is heated with P2O5, it forms
N2O
NO
NO2
N2O5
The mixture of conc.HCl and HNO3 made 3:1 ratio contains
ClO2
NOCl
NCl3
N2O4
PH3, the hydride of phosphorus is
metallic
ionic
non-metallic
covalent
In the alumino-thermite process, Al acts as
Flux
Oxidizing agent
Reducing agent
Promoter
Hydrogen will not reduce
heated cupric oxide
heated ferric oxide
heated stannic oxide
heated aluminium oxide
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
Red lead is
PbO
Pb3O4
PbO2
Pb4O3
Which of the following is most stable ?
Sn2+
Ge2+
Si2+
Pb2+
