Medium MCQ +4 / -1 PYQ · JEE Mains 2021

The correct order of conductivity of ions in water is :

  1. A K<sup>+</sup> &gt; Na<sup>+</sup> &gt; Cs<sup>+</sup> &gt; Rb<sup>+</sup>
  2. B Cs<sup>+</sup> &gt; Rb<sup>+</sup> &gt; K<sup>+</sup> &gt; Na<sup>+</sup> Correct answer
  3. C Na<sup>+</sup> &gt; K<sup>+</sup> &gt; Rb<sup>+</sup> &gt; Cs<sup>+</sup>
  4. D Rb<sup>+</sup> &gt; Na<sup>+</sup> &gt; K<sup>+</sup> &gt; Li<sup>+</sup>

Solution

As the size of gaseous ion decreases, it get more hydrated in water and hence, the size of aqueous ion increases. When this bulky ion move in solution, it experience greater resistance and hence lower conductivity.

About this question

Subject: Chemistry · Chapter: s-Block Elements · Topic: Alkali Metals

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