Question

Assume that you are going to present a seminar on transition elements. Prepare a seminar paper by stressing any four important properties of transition elements.

Answer 1

The transition elements are the elements in groups 3 – 12 of the periodic table in which the d – orbitals are progressively filled.

1) Magnetic properties : Most of transition elements show paramagnetism due to the presence of unpaired electrons. The magnetic moment

(μ)μ = \(\sqrt{n(n+2)}\)

2) Formation of coloured ions : Transition elements form coloured compounds due to the presence of unpaired d – electrons, which can take part in d – d transition.

3) Formation of complex compounds: Transition metals form a large number of complex compounds. This is due to the comparatively smaller sizes of the metal ions, their high ionic charges and the availability of d – orbitals for bond formation, 

e.g., K₄[Fe(CN)₆], [Co(NH₃)₆]CI₃

4) Catalytic properties : Transition elements and their compounds act as good catalysts. This is attributed to their ability to adopt show multiple oxidation states because of and to form complexes due to the presence of partially filled d – orbitals, 

e.g., Finely divided Fe is used as a catalyst in Haber’s process.