Question
Why the tansition elements are hard and have high melting and boiling points?
✓
Answer
$\rightarrow$ The high melting points of these 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.
$\rightarrow$ In any row the melting points of these metals rise to a maximum at $d^5$ except for anomalous values of $Mn$ and $Te$ and fall regularly as the atomic number increases.
Trends in melting points of transition elements
$\rightarrow Zn, Cd,$ and $Hg$ are soft and volatile and they have low melting point because all these elements have no unpaired electrons.
$\rightarrow$ In any row the melting points of these metals rise to a maximum at $d^5$ except for anomalous values of $Mn$ and $Te$ and fall regularly as the atomic number increases.
Trends in melting points of transition elements
$\rightarrow Zn, Cd,$ and $Hg$ are soft and volatile and they have low melting point because all these elements have no unpaired electrons.
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