CBSE
Argon is used
in filling airships
to obtain low temperature
in high temperature welding
in radiotherapy for treatment of cancer
Consider the following reaction,
C6H5NO2 X Y + HCl
What is Y?
Acetanilide
Benzinilide
Azobenzene
Hydrazobenzene
In long form of Periodic Table, the properties of the elements are a periodic function of their
atomic size
ionisation energy
atomic mass
atomic number
The most basic element is
fluorine
iodine
chlorine
bromine
The metal that produces red-violet colour in the non-luminous flame is
Ba
Ag
Rb
Pb
Which one of the following transition metal ions is diamagnetic?
Co2+
Ni2+
Cu2+
Zn2+
Which of the following configurations corresponds to element of highest ionisation energy?
1s2, 2s1
1s2, 2s2, 2p3
1s2, 2s2, 2p2
1s2, 2s2, 2p6, 3s1
Which of the following is a wrong statement ? In a given period of the Periodic Table, the s-block element has, in general, a higher value of
electronegativity
atomic radius
ionisation energy
electron affinity
The element which forms oxides in all oxidation states + 1 to + 5 is
nitrogen
phosphorus
arsenic
antimony
The correct order of decreasing first ionisation energy is
C > B > Be > Li
C > Be > B > Li
B > C > Be > Li
Be > Li > B > C