1. The d-block elements are also known as _________ metals.

2. Transition metals often have multiple ____________ states.

3. In the periodic table, the d-block elements are located between the ___________ and ___________ blocks.

4. The outermost electrons of transition metals are found in the ____________ orbitals.

5. Transition metals are known for their high ___________ and ___________ points.

6. Transition metals are good ___________ of heat and electricity.

7. ___________ complexes involve a central metal atom/ion bonded to surrounding ligands.

8. Iron (Fe) is an example of a ___________ metal.

9. The lanthanides are located in period ___________ of the periodic table.

10. Actinides are found in period ___________ of the periodic table.

11. The lanthanides are sometimes referred to as ___________ earth elements.

12. ___________ is a property exhibited by actinides due to their unstable atomic nuclei.

13. Uranium-235 is commonly used in ___________ reactions.

14. ___________ is the process by which heavy atomic nuclei split into smaller nuclei, releasing energy.

15. The lanthanide contraction results in a progressive decrease in atomic and ___________ radii.

16. Lanthanides have similar ___________ properties due to their nearly identical electron configurations.

17. In coordination compounds, lanthanides often form complexes with similar ___________ geometries.

18. The lanthanide series begins with ___________ and ends with ___________.

19. The actinide series includes elements from ___________ to ___________.

20. The lanthanide and actinide series are part of the ___________ elements in the periodic table.