Actinoid contraction is greater from element to element than lanthanoid contraction Why?

Explanation

To understand why actinoid contraction is greater than lanthanoid contraction, we can break down the explanation into several steps:

### Step 1: Define Actinoid and Lanthanoid Contraction
Actinoid contraction refers to the gradual decrease in the size of the actinide elements (elements 89 to 103) as you move from element to element in the periodic table. Similarly, lanthanoid contraction refers to the decrease in size of the lanthanide elements (elements 57 to 71).

### Step 2: Understand the Role of Electrons
Both actinoids and lanthanoids have f-orbitals that are being filled as we move across the series. The actinoids fill the 5f orbitals, while the lanthanoids fill the 4f orbitals.

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