Ncert Exercises & Solutions

Given below are two statements:

Assertion (A):	E_cell should have a positive value for the cell to function.
Reason (R):	E_cathode < E_anode

1.	Both (A) and (R) are True and (R) is the correct explanation of (A).
2.	Both (A) and (R) are True but (R) is not the correct explanation of (A).
3.	(A) is True but (R) is False.
4.	(A) is False but (R) is True.

Hint: E_cell should have a positive value for the cell to function.

Feasibility of chemical reaction depends on Gibbs free energy which is related to E_cell as

∆

G = -nFE_cell

When the value of E_cell is positive then

∆

G becomes negative. Hence, the reaction becomes feasible. Hence, the Assertion is true.

But E_cathode < E_anode is not compulsory. Thus, the Assertion is true but the reason is false.