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
A.
0.84
From Kjeldahl's method,
percentage of nitrogen =
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