JEE Main202312 Apr 2023Morning ShiftChemistryGeneral Principles and Processes of Isolation of MetalsActual
Given below are two statements: one is labelled as Assertion A and the other is labelled as Reason R Assertion A: In the Ellingham diagram, a sharp change in slope of the line is observed from Mg → MgO at ~ 1120 o C Reason R: There is a large change of entropy associated with the change of state In the light of the above statements, choose the correct answer from the options given below
Options
- ABoth A and R are true but R is NOT the correct explanation of A
- BA is false but R is true
- CBoth A and R are true and R is the correct explanation of A
- DA is true but R is false
Correct answer
C. Both A and R are true and R is the correct explanation of A
Step-by-step solution
For line II ∆ S is more negative than line I. In the Ellingham diagram, a sharp change in slope of the line is observed for Mg - MgO at ~ 1120 o C because that is the boiling point of magnesium. From diagram, ∆ S I = ( S solid ) - ( S solid + S gas ) ∆ S II = ( S liquid ) - ( S solid + S gas ) There is a large increase in entropy associated with the change of state of magnesium. So, both Assertion (A) and Reason (R) are true and (R) is the correct explanation of (A).