CBSE
HCl is a gas but HF is a low boiling liquid .This is because :
H-F bond is strong
H-F bond is weak
molecules aggregate because of hydrogen bonding
HF is a weak acid
Which of the following is the correct statement for PH3?
It is less poisonous than NH3.
It is less basic than NH3.
Electronegativity of PH3 >NH3.
It does not show reducing properties.
Which oxide of nitrogen is coloured gas ?
N2O
NO2
N2O5
NO
The substance used in smoke screen is :
sodium chloride
sodium phosphate
calcium fluoride
calcium phosphide
Which will not form precipitation after addition of (NH4)2CO3 in presence of NH4Cl?
Mg
Ba
Sn
Sr
Difference in atomic radius is maximum for
Rb-Cs
K-Rb
Na-K
Li-Na
Ostwald process is used for the manufacture of :
nitric acid
sulphuric acid
ammonia
bleaching powder
Which of the following inert gas liquifies easily ?
He
Kr
Ne
Ar
The chemical used for cooling in refrigerators is :
CO2
NH4OH
NH4Cl
liquid NH3
Which is correct order of solubility in water?
Ba(OH)2 <Mg(OH)2
BaCO3> CaCO3
CaSO4 <MgSO4
Ca(OH)2Mg(OH)2