The temporary hardness of a water sample is due to compound X. Boiling this sample converts X to compound Y. X and Y, respectively, are:

This question was previously asked in
JEE Mains Previous Paper 1 (Held On: 12 Apr 2019 Shift 2)
View all JEE Main Papers >
  1. Mg(HCO3)2 and Mg(OH)2
  2. Ca(HCO3)2 and Ca(OH)2
  3. Mg(HCO3)2 and MgCO3
  4. Ca(HCO3)2 and CaO

Answer (Detailed Solution Below)

Option 1 : Mg(HCO3)2 and Mg(OH)2
Free
JEE Main 04 April 2024 Shift 1
90 Qs. 300 Marks 180 Mins

Detailed Solution

Download Solution PDF

Concept:

The temporary hardness is caused by bicarbonates of calcium and magnesium. On boiling following changes occurs,

On boiling, the bicarbonates salt of magnesium Mg(HCO3)2, the solution produces the magnesium hydroxide to decompose and yielding carbon dioxide and hydrogen.

Calcium hydrogen carbonate on boiling will produce calcium carbonate with carbon dioxide and hydrogen.

X = Mg(HCO3)2

Y = Mg(OH)2

Latest JEE Main Updates

Last updated on Jul 11, 2025

 

-> JEE Main 2026 application will start probably from second week of October 2025 till November 2025.

->Check JEE Main syllabus for 2026 examination.

-> JEE Main is a national-level engineering entrance examination conducted for 10+2 students seeking courses B.Tech, B.E, and B. Arch/B. Planning courses. 

-> JEE Mains marks are used to get into IITs, NITs, CFTIs, and other engineering institutions.

-> All the candidates can check the JEE Main Previous Year Question Papers, to score well in the JEE Main Exam 2025. 

Hot Links: teen patti master purana teen patti master 2023 teen patti club teen patti casino