d and f BLOCK ELEMENTS

Why is the third ionization enthalpy of Fe considered lower than that of Mn?

• Because the second ionization enthalpy of Fe2+ (d6 to d5) is lower than the second ionization enthalpy of Mn2+ (d5 to d4)
• Because the second ionization enthalpy of Mn2+ (d5 to d4) is lower than the second ionization enthalpy of Fe2+ (d6 to d5)
• Because Fe has a higher atomic number
• Because Mn has a lower atomic radius

What is the electronic configuration of the Mn2+ ion?

• 3d5
• 3d3 4s2
• 3d7
• 3d6

In the formation of M2+ ions from gaseous transition metal atoms, which enthalpy term is described as the dominant factor influencing the process?

• Second ionisation enthalpy
• First ionisation enthalpy
• Enthalpy of atomisation
• Sum of first and second ionisation enthalpies

Which first-row transition metal commonly exhibits both +2 and +3 oxidation states as its most prevalent forms?

• Iron (Fe)
• Cobalt (Co)
• Nickel (Ni)
• Manganese (Mn)

Which first-row transition metal predominantly exhibits only the +2 oxidation state in its common chemistry?

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