Question

Give reasons for the following : 

(a) Transition metals have high enthalpies of atomization. 

(b) Manganese has lower melting point even though it has a higher number of unpaired electrons for bonding. 

 (c) Ce⁴⁺ is a strong oxidizing agent. 

Answer 1

(a) Transition elements have a large number of valence electrons and high effective nuclear charge. Due to this they form very strong metallic bonds. As a result of this the enthalpy of atomization of transition metals is high. 

(b) Complex structure of metal crystal is responsible for this abnormal behaviour of manganese. 

(c) Ce⁴⁺(4f ⁰ ) in + 4 oxidation state tend to revert to the more stable oxidation state of + 3 by gain of an electron so it behaves as strong oxidising agent.