Question

What is meant by inner transition elements?

Answer 1

• The elements with atomic numbers 89 to 103 of period 7 are given separate positions at the bottom of the periodic table. These elements are called inner transition elements.
• Inner transition elements from Lanthanum (La) to Lutetium (Lu) of period 6 are called lanthanides. Inner transition elements from Actinium (Ac) to Lawrencium (Lr) of period 7 are called actinoids.
• Lanthanoids are also called rare earth. Actinoids are man-made artificial elements (except thorium and uranium).