d and f BLOCK ELEMENTS

What is the primary reason for the deviation of Zn's E°(M2+/M) value from the general trend across the transition series?

• Its low atomic mass.
• Its high ionization enthalpy.
• Its low hydration enthalpy.
• The formation of a stable, fully filled d10 electronic configuration in Zn2+.

Why is the hydration enthalpy of Cu2+ considered relatively low?

• Because Cu2+ has a small ionic radius.
• Because Cu2+ has a low charge density.
• Because water molecules do not interact strongly with transition metal ions.
• Because the 3d electrons in Cu2+ provide poor shielding, making the effective nuclear charge felt by the incoming water molecules higher.

How does the high atomization enthalpy of copper relate to its metallic bonding?

• Weak metallic bonding allows easy atomization.
• Ionic bonding is primarily responsible for copper's properties.
• Covalent bonding within the layers makes atomization difficult.
• Strong metallic bonding in copper requires more energy to break apart the solid lattice into gaseous atoms.

What is the significance of the half-filled d5 configuration in the context of Mn chemistry?

• It makes Mn2+ highly reactive and unstable.
• It makes Mn3+ a strong reducing agent.
• It has no significant impact on Mn's redox behavior.
• It provides extra stability to the Mn2+ ion, making Mn3+ a strong oxidizing agent.

Which of the following best describes the stability gained when Mn3+ (d4) is reduced to Mn2+ (d5)?

• Stabilization due to a fully filled d subshell.
• Stabilization due to a half-filled t2g level.
• Stabilization due to pairing of electrons in the eg level.
• Stabilization due to a half-filled d subshell in the d5 configuration.