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.


Electricity is passed through an acidic solution of Cu$^{2+}$ till all the Cu$^{2+}$ was exhausted, leading to the deposition of 300 mg of Cu metal. However, a current of 600 mA was continued to pass through the same solution for another 28 minutes by keeping the total volume of the solution fixed at 200 mL. The total volume of oxygen evolved at STP during the entire process is ___ mL. (Nearest integer)
Given:
$\mathrm{Cu^{2+} + 2e^- \rightarrow Cu(s)}$
$\mathrm{O_2 + 4H^+ + 4e^- \rightarrow 2H_2O}$
Faraday constant = 96500 C mol$^{-1}$
Molar volume at STP = 22.4 L