General characteristics of transition elements.
(i) Electronic configuration – (n – 1)d1−10ns1−2
(ii) Metallic character - With the exceptions of Zn, Cd and Hg, they havetypical metallic structures.
(iii) Atomic and ionic size - Ions of same charge in a given series showprogressive decrease in radius with increasing atomic number.
(iv) Oxidation state - Variable ; ranging from +2 to +7.
(v) Paramagnetism - The ions with unpaired electrons are paramagnetic.
(vi) Ionisation enthalpy - Increases due to increase in molecular charge.
(vii) Formation of coloured ions - Due to unpaired electrons.
(viii) Formation of complex compounds - Due to small size and highcharge density of metal ions.
(ix) They possess catalytic properties - Due to their ability to adoptmultiple oxidation states.
(x) Formation of interstitial compounds.
(xi) Alloy formation.They are called transition elements due to their incompletely filledd-orbitals in ground state or any stable oxidation state and they areplaced between s and p-block elements. Zn, Cd and Hg have fully filledd‌0configuration in their ground state hence may not be regarded as thetransition elements.