d and f BLOCK ELEMENTS

What is a key reason why the lowest oxides of transition metals tend to be basic?

• The metal is in a high oxidation state and strongly attracts electrons.
• They readily accept protons.
• They are always ionic compounds.
• The metal is in a low oxidation state and can easily donate electrons or oxide ions.

Why is the d1 electron configuration considered very unstable in ions?

• It readily gains nine electrons to achieve a stable d10 configuration.
• It readily loses the single d-electron to achieve the stable d0 configuration.
• It forms stable complexes easily.
• It is stable due to minimal electron-electron repulsion.

For the d4 configuration, why is Cr2+ considered strongly reducing while Mn3+ is considered strongly oxidizing?

• Both are strongly reducing
• Cr2+ (d4) can easily lose an electron to achieve a stable d3 (half-filled) configuration, while Mn3+ (d4) can gain an electron to achieve a stable d5 (half-filled) configuration.
• Both are strongly oxidizing
• Their redox properties are unrelated to their d-electron count

Among the first transition series elements, which metal exhibits the +1 oxidation state most frequently?

• Scandium (Sc)
• Titanium (Ti)
• Copper (Cu)
• Zinc (Zn)

Based on the provided E° values, which metal is easiest to oxidize from its metallic state (M) to M2+ ions?

• Iron (Fe)
• Chromium (Cr)
• Manganese (Mn)
• They are equally easy