The second and third rows of transition elements resemble each other much more than they resemble the first row. Explain, why?

Explanation

To explain why the second and third rows of transition elements resemble each other much more than they resemble the first row, we can follow these steps:

### Step 1: Identify the Transition Element Series
The transition elements are divided into three series based on their electron configurations:
- The first row (3D series) includes elements from Scandium (Sc) to Zinc (Zn).
- The second row (4D series) includes elements from Yttrium (Y) to Cadmium (Cd).
- The third row (5D series) includes elements from Lanthanum (La) to Mercury (Hg).

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