The melting and boiling points of Zn, Cd, and Hg are low.
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Solution and Explanation
Step 1: Electronic Configuration and Bonding - Zn, Cd, and Hg belong to Group 12 and have a completely filled d\(^ {10}\) configuration. - The lack of unpaired d-electrons reduces the extent of metallic bonding, making these metals soft with low melting and boiling points.
Step 2: Weak Interatomic Forces - In transition metals, strong metallic bonding arises due to overlapping of d-orbitals. - However, in Zn, Cd, and Hg, fully filled d-orbitals do not contribute to bonding, resulting in weak interatomic forces and low melting/boiling points.
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