The incorrect statement in respect of chromyl chloride test is
formation of red vapours
formation of lead chromate
formation of chromyl chloride
liberation of chlorine
In Kjeldahl's method, ammonia from 5 g of food neutralizes 30 cm3 of 0.1 N acid. The percentage of nitrogen in the food is
0.84
8.4
16.8
1.68
In Ramsay and Rayleigh's isolation of noble gases from air, the nitrogen of the air is finally converted into
NaNO2 only
NO and NO2
NaNO3 only
NaNO2 and NaNO3
A white crystalline salt A reacts with dilute HCl to liberate a suffocating gas B and also forms a yellow precipitate. The gas B turns potassium dichromate acidified with dilute H2SO4 to a green coloured solution C. A, B, C are respectively
Na2SO3, SO2, Cr2(SO4)3
Na2S2O3, SO2, Cr2(SO4)3
Na2SO2 , SO2, Cr2(SO4)3
Na2SO4, SO2, Cr2(SO4)3
Molecules of a noble gas do not possess vibrational energy because a noble gas
is monoatomic
is chemically inert
has completely filled shells
is diamagnetic
Which one of the following sets of ions represents the collection of isoelectronic species?
K+, Cl-, Mg2+, Sc3+
Na+, Ca2+, Sc3+, F-
K+, Ca2+, Sc3+,Cl-
Na+, Mg2+, Al3+, Cl-
When formic acid is heated with conc. H2SO4 the gas evolved is
Only CO2
Only CO2
mixture of CO and CO2
a mixture of SO2 and CO2
excess of PCl5 reacts with concentrated H2SO4 giving
chlorosulphuric acid
sulphurous acid
sulphury chloride
thionyl chloride