Define Lanthanoid Contraction and Mention its Consequences

Answer: The Lanthanide Contraction refers to the Lanthanide series’ atomic radius trend. Another aspect of the Lanthanide Contraction is that the 5s and 5p orbitals pierce the 4f sub-shell, exposing the 4f orbital to the rising nuclear change, causing the atomic radius to shrink. Throughout the series, this shrinking in size is maintained.

• Atomic size: The atoms of the third transition series are nearly identical in size to those of the second transition series.
• Complex formation: The tendency to create coordinates is because of the smaller size but larger nuclear charge.
• FromLa to Lu, the electronegativity increases.