d and f BLOCK ELEMENTS

Why is the highest oxidation state of a transition metal typically exhibited in its oxide or fluoride compounds?

• Oxygen and fluorine are large atoms
• Oxygen and fluorine have a strong tendency to donate electrons
• Oxygen and fluorine are metallic
• Oxygen and fluorine are inert

Which of the following first-row transition metal ions is expected to be a strong reducing agent based on its E°(M3+/M2+) value?

• Fe2+
• Mn2+
• Co2+
• Cr2+

What is the main factor determining the decreasing tendency to form divalent cations (M2+) across the first transition series?

• Decrease in atomic radius
• Increase in hydration energy
• Decrease in electron affinity
• Increase in the sum of first and second ionisation enthalpies

Which of the following statements best describes the magnetic properties of substances?

• Diamagnetic substances are attracted, paramagnetic substances are repelled
• Diamagnetic substances are repelled, paramagnetic substances are attracted
• All substances are attracted equally
• All substances are repelled equally

Why are the E°(M2+/M) values for Mn, Ni, and Zn more negative than expected from the general trend across the first transition series?

• Lower atomic masses
• Higher melting points
• Stable d5 (Mn2+) and d10 (Zn2+) configurations and hydration enthalpy (Ni)
• Smaller ionic radii