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NEETChemistryd and f Block Elements

What causes the actinoid contraction across the series?

Options

  1. AIncrease in atomic number
  2. BDecrease in atomic number
  3. CPoor shielding by 5f electrons
  4. DStrong shielding by 4f electrons

Correct answer

C. Poor shielding by 5f electrons

Step-by-step solution

The actinoid contraction is caused by poor shielding by 5f electrons.

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