d and f BLOCK ELEMENTS

Why is the third ionization enthalpy of Lanthanum (La) abnormally low?

• High nuclear charge
• Large atomic radius
• Stability of the empty f level
• Low first ionization enthalpy

What contributes to the stability of certain f-orbital configurations in lanthanoids, affecting ionization enthalpies?

• Hydration enthalpy
• Lattice enthalpy
• Exchange enthalpy considerations
• Electron affinity

What is the approximate value of the second ionization enthalpy for lanthanoids?

• About 600 kJ mol⁻¹
• About 900 kJ mol⁻¹
• About 1200 kJ mol⁻¹
• About 1500 kJ mol⁻¹

What is the approximate value of the first ionization enthalpy for lanthanoids?

• Around 400 kJ mol⁻¹
• Around 600 kJ mol⁻¹
• Around 800 kJ mol⁻¹
• Around 1000 kJ mol⁻¹

What is the magnetic nature of lanthanoid ions that are not of the f⁰ or f¹⁴ types?

• Diamagnetic
• Ferromagnetic
• Paramagnetic
• Antiferromagnetic