Question

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 :
(A) Mg(HCO₃)₂ and MgCO₃ (B) Ca(HCO₃)₂ and CaO
(C) Mg(HCO₃)₂ and Mg(OH)₂ (D) Ca(HCO₃)₂ and Ca(OH)₂

Answer 1

Answer:

Option C is the answer

Explanation:

heyo!

Btw, this is a previous mains question may be 2019 one. And an ABSOLUTE  NCERT question. This is a point we often overlook while reading ncert.

Okay, remember,  Mg(oh)2 has low solubility then mgco3 so actually, we would have predicted mg(hco3)2  to get converted into mgco3+co2+h2o but because of this reason, it stays as mg(oh)2 only. But if its  Ca(hco3)2,  caco3 is only ppt.  So, this is an important point to be remembered.

Refer to ncert if any doubts left.Its  1st year syllabus from hydrogen and its  compounds lesson.

Any doubts welcome

hope this helps:))