CBSE Class 12 · 2023 · d and f Block ElementsMultiple Choice

Transition metals are known to form interstitial compounds. The formation of interstitial compounds makes the transition metal:

Assertion (A): Zr and Hf have almost similar atomic radii.
Reason (R): This is due to lanthanoid contraction.

Which of the following ions has the electronic configuration 3d${}^6$? (Atomic numbers: Mn = 25, Co = 27, Ni = 28)

(a) A transition element X has the electronic configuration [Ar]4s²3d³. Predict its likely oxidation states.

a) Write any two consequences of lanthanoid contraction.
b) Name the element of the 3d series which exhibits the largest number of oxidation states. Give a reason.

Give reasons for the following statements:
a) Scandium (Z = 21) is a transition element but Zn (Z = 30) is not.
b) [Ti(H₂O)₆]³⁺ is coloured while [Sc(H₂O)₆]³⁺ is colourless.
c) The physical and chemical properties of the 4d and 5d series of transition elements are more similar th …