The lower block transition elements are called the ________________ and the ___________________

The lower block transition elements are called the lanthanides and the actinides.

Explanation:

• The lanthanides consist of the 15 chemical elements from lanthanum (La) to lutetium (Lu), which are found in the f-block of the periodic table. They are known for their similar properties, including their high magnetic susceptibility and the ability to produce bright colors in certain compounds.

• The actinides include the 15 elements from actinium (Ac) to lawrencium (Lr). These elements are also found in the f-block and are characterized by their radioactivity and the ability to form transuranium elements through nuclear reactions.

Both series are essential for understanding various chemical behaviors and applications in fields such as materials science, energy, and nuclear chemistry.