Question

In first transition series, the melting point of $Mn$ is low because.

• A. Due to $d^{10}$ configuration, metallic bonds are strong
• B. Due to $d^{7}$ configuration, metallic bonds are weak
• C. Due to $d^{5}$ configuration, metallic bonds are weak
• D. None of these

Answer 1

Answer: (C)

Due to $d^{5}$ configuration, metallic bonds are weak

Answer 2

Due to $d^{5}$ configuration, metallic bonds are weak. $d^{5}$ orbital is half filled as a result $3d$ electrons are more tightly held by the nucleus and this reduces the de-localization of electrons resulting in weaker metallic bonding.