Question

Transition elements have high MP & BP due to:

• A. use of ns electrons
• B. use of (n-1)d electrons only
• C. both ns and (n-1)d electrons
• D. use of np electrons

Answer 1

The correct option is C both ns and (n-1)d electrons

The high melting and boiling points of d-block metals are attributed to the involvement of greater number of electrons from (n-1)d in addition to the ns electrons in the interatomic metallic bonding. In any row the melting points of these metals rise to a maximum at $d^5$ except for anomalous values of Mn and Tc and fall regularly as the atomic number increases.