Multiple Choice QuestionsIn the periodic table actinides occupy :
III B group in 7th row
III B group in 6th row
III B group in 5th row
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
B.
3d - orbitals are empty in its stable compound
Outer electronic configuration of Sc is 3d1 , 4s2
In the stable oxidation state ie , +3 , the electronic configuration of sc3+ is ;
Sc3+ : 1s2 , 2s2 2p6 , 3s2 3p6 3d0
It shows that 3d subshell is empty transition element can refer to those elements which form atleast one ion with a partially filled d shell of electrons .As Sc3+ has no electrons in its d orbital , hence , it is not considered as transition element in the stricter sense .
The 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
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
In the periodic table metals usually used as catalysts belong to :
f - block
d - block
p - block
s - block
In a neutron induced reaction of , the product obtained is , three neutrons and an element (new nuclide) .The other new nuclide is :
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