JEE Main 2021 — Ionic Equilibrium Question with Solution
From: JEE Main 2021 (Online) 18th March Morning Shift
Question
Given below are two statements : One is labelled as Assertion A and the other labelled as reason R
Assertion A : During the boiling of water having temporary hardness, Mg(HCO3)2 is converted to MgCO3.
Reason R : The solubility product of Mg(OH)2 is greater than that of MgCO3.
In the light of the above statements, choose the most appropriate answer from the options given below :
Assertion A : During the boiling of water having temporary hardness, Mg(HCO3)2 is converted to MgCO3.
Reason R : The solubility product of Mg(OH)2 is greater than that of MgCO3.
In the light of the above statements, choose the most appropriate answer from the options given below :
Choose an option
Show full solutionCorrect option: D
Correct answer
DA is false but R is true
Step-by-step explanation
A : For temporary hardness,
Mg(HCO3)2 Mg(OH)2 + 2CO2 Assertion is false. MgCO3 has high solubility product than Mg(OH)2.
R : MgCO3 is more water soluble than Mg(OH)2.
KSP(Mg(OH)2) = 1.8 × 10–11
KSP(MgCO3) = 3.5 × 10–8
Mg(HCO3)2 Mg(OH)2 + 2CO2 Assertion is false. MgCO3 has high solubility product than Mg(OH)2.
R : MgCO3 is more water soluble than Mg(OH)2.
KSP(Mg(OH)2) = 1.8 × 10–11
KSP(MgCO3) = 3.5 × 10–8
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