Easy MCQ +4 / -1 PYQ · JEE Mains 2025

Choose the incorrect trend in the atomic radii (r) of the elements.

  1. A <p><i>r</i><sub>Rb</sub> &lt; <i>r</i><sub>Cs</sub></p>
  2. B <p><i>r</i><sub>At</sub> &lt; <i>r</i><sub>Cs</sub></p>
  3. C <p><i>r</i><sub>Br</sub> &lt; <i>r</i><sub>K</sub></p>
  4. D <p><i>r</i><sub>Mg</sub> &lt; <i>r</i><sub>Al</sub></p> Correct answer

Solution

<p>In a period (row on the periodic table), the atomic size generally decreases as you move from left to right. This is because additional electrons are being added to the same outer shell while the number of protons in the nucleus increases, pulling the electron cloud closer to the nucleus and reducing the atomic radii.</p>

About this question

Subject: Chemistry · Chapter: Periodic Table and Periodicity · Topic: Periodic Trends

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