Easy MCQ +4 / -1 PYQ · JEE Mains 2022

Boiling of hard water is helpful in removing the temporary hardness by converting calcium hydrogen carbonate and magnesium hydrogen carbonate to :

  1. A CaCO<sub>3</sub> and Mg(OH)<sub>2</sub> Correct answer
  2. B CaCO<sub>3</sub> and MgCO<sub>3</sub>
  3. C Ca(OH)<sub>2</sub> and MgCO<sub>3</sub>
  4. D Ca(OH)<sub>2</sub> and Mg(OH)<sub>2</sub>

Solution

$$\mathrm{Ca}\left(\mathrm{HCO}_{3}\right)_{2} \stackrel{\Delta}{\longrightarrow} \mathrm{CaCO}_{3} \downarrow+\mathrm{H}_{2} \mathrm{O}+\mathrm{CO}_{2} \uparrow$$<br/><br/> $$\mathrm{Mg}\left(\mathrm{HCO}_{3}\right)_{2} \stackrel{\mathrm{A}}{\longrightarrow} \mathrm{Mg}(\mathrm{OH})_{2}+2 \mathrm{CO}_{2} \uparrow$$

About this question

Subject: Chemistry · Chapter: p-Block Elements · Topic: Group 13: Boron Family

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