d and f BLOCK ELEMENTS

Which of the following 3d metal trihalides is mentioned as existing in the provided text?

• TiX₃
• VX₃
• CrX₃
• FeX₃

Why does the standard electrode potential (E°) for the reduction of Mn²⁺ to Mn have a relatively low negative value compared to its neighbors?

• Due to the instability of the Mn²⁺ ion
• Due to the high ionization energy of Mn
• Due to the low hydration energy of Mn²⁺
• Due to the stability of the half-filled d⁵ subshell in the Mn²⁺ ion

Which element among the first-row transition metals has a standard electrode potential (E°) for M²⁺/M closest to zero?

• Fe
• Co
• Ni
• Cu

What is the standard electrode potential (E°) for the reduction of Zn²⁺ to Zn?

• -0.25 V
• -0.44 V
• 0.34 V
• -0.76 V

According to the provided data, which first-row transition metal has the most negative hydration enthalpy (DhydH°) for its M²⁺ ion?

• Ti
• Cr
• Fe
• Ni