JEE Main202118 Mar 2021Morning ShiftChemistryHydrogenActual
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 HCO 3 2 is converted to MgCO 3 Reason R : The solubility product of Mg ( OH ) 2 is greater than that of MgCO 3 . In the light of the above statements, choose the most appropriate answer from the options given below:
Options
- ABoth A and R are true but R is not the correct explanation of A
- BA is true but R is false
- CBoth A and R are true and R is the correct explanation of A
- DA and R both are false.
Correct answer
D. A and R both are false.
Step-by-step solution
For temporary hardness, Mg HCO 3 2 ⟶ heating Mg OH 2 ↓ + 2 CO 2 ↑ Assertion is false. MgCO 3 has high solubility product than Mg ( OH ) 2 . According to data of NCERT table 7 . 9 (Equilibrium chapter), the solubility product of magnesium carbonate is 3 . 5 × 10 - 8 and solubility product of Mg ( OH ) 2 is 1 . 8 × 10 - 11 Hence Reason is incorrect.