CBSE
Multiple Choice QuestionsThe properties of Zr and Hf are same because :
they have similar radii
they belong to d-block
they have same valence electrons
None of the above
Why Sc (Z = 21) is not considered as transition element ?
Properties of Sc are similar to alkali metals
3d - orbitals are empty in its stable compound
Stable oxidation number of Sc is +2
Atomic volume of Sc is very large
The electronic configuration of Cr3+ is :
[Ar] 3d4 4s2
[Ar] 3d3 4s0
[Ar] 3d2 4s1
[Ar] 3d5 4s1
The atomic number of Ni and Cu are 28 and 29 respectively .The electronic configuration 1s , 2s2 2p6 , 3s2 3p6 3d10 represents :
Cu+
Cu2+
Ni2+
Ni
Formation of coloured solution is possible when metal ion in the compound contains :
paired electrons
lone pair of electrons
unpaired electrons
None of the above
Assertion : Transition metals are poor reducing agents.
Reason : Transition metals form numerous alloys
with other metals.
If both assertion and reason are true and reason is the correct explanation of assertion.
If both assertion and reason are true but reason is not the correct explanation of assertion.
If assertion is true but reason is false.
If both assertion and reason are false.
The lanthanide contraction is responsible for the fact that :
Zr and Zn have the same oxidation state
Zr arid Hf have about the same radius
Zr and Nb have similar oxidation state
Zr and Y have about the same radius
In a neutron induced reaction of , the product obtained is , three neutrons and an element (new nuclide) .The other new nuclide is :
In the periodic table metals usually used as catalysts belong to :
f - block
d - block
p - block
s - block
Which of the following forms a colourless solution in aqueous medium ?
Cr3+
V3+
Sc3+
Ti3+
