Question

The actinoids exhibit more number of oxidation states in general than the lanthanoids. This is because ______.

Options

• the 5f-orbitals are more buried than the 4f-orbitals

• there is a similarity between 4f and 5f-orbitals in their angular part of the wave function.

• the actinoids are more reactive than the lanthanoids.

• the 5f-orbitals extend farther from the nucleus than the 4f-orbitals.

Answer 1

The actinoids exhibit more number of oxidation states in general than the lanthanoids. This is because the 5f-orbitals extend farther from the nucleus than the 4f-orbitals.

Explanation:

The energy of the 5f-orbitals is similar to that of the 6d-orbitals because they are farther from the nucleus than the 4f-orbitals. As a result, actinoids use both 5f and 6d orbitals and have more oxidation states than lanthanoids.