d and f BLOCK ELEMENTS

Based on E°(M3+/M2+) values, what is the order of oxidising strength (strongest to weakest) for these ions in aqueous solution?

• Fe3+ > Co3+ > Mn3+
• Co3+ > Mn3+ > Fe3+
• Mn3+ > Co3+ > Fe3+
• Cr3+ > V3+ > Ti3+

Which of the following best describes the chemical reactivity of Titanium (Ti) and Vanadium (V) with dilute non-oxidising acids at room temperature?

• They react rapidly
• They are noble metals
• They are practically passive, despite having negative E°(M2+/M) values
• They form insoluble salts

What is the significance of a positive E° value for a metal like Copper (Cu)?

• It indicates high melting point
• It indicates high density
• It indicates Cu is less reactive than hydrogen towards H+ ions
• It indicates strong paramagnetism

Why is the E°(M2+/M) value for Manganese (Mn) more negative than expected from the general trend?

• High atomic radius
• Low density
• High melting point
• The stability of the half-filled d5 configuration in Mn2+

Why is the E°(M2+/M) value for Zinc (Zn) more negative than expected from the general trend?

• High first ionisation enthalpy
• Low atomic mass
• Low melting point
• The stability of the completely filled d10 configuration in Zn2+