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NEET CHEMISTRYElectrochemistryEasy

Question

A cell reaction becomes spontaneous when:

A

ΔG\Delta G^{\circ} is negative

B

ΔG\Delta G^{\circ} is positive

C

ERedE^{\circ}_{Red} is positive

D

ERedE^{\circ}_{Red} is negative

Step-by-Step Solution

The spontaneity of a reaction is determined by the Gibbs free energy change (ΔG\Delta G). For a cell reaction to be spontaneous, the free energy of the system must decrease, which means ΔG\Delta G (or ΔG\Delta G^{\circ} under standard conditions) must be negative. The relationship between standard Gibbs free energy and standard cell potential is given by the equation: ΔG=nFEcell\Delta G^{\circ} = -nFE^{\circ}_{cell}. Since nn (number of moles of electrons) and FF (Faraday constant) are positive values, ΔG\Delta G^{\circ} will be negative only when the overall cell potential EcellE^{\circ}_{cell} is positive.

Exam Context & Concepts Covered

This question aligns with the NEET CHEMISTRY syllabus, specifically targeting concepts from Electrochemistry. Mastering this topic is crucial for scoring well in the upcoming medical entrance examinations. Solving conceptually related problems will help you understand the nuances of these concepts and improve your problem-solving speed.

CHEMISTRYElectrochemistryreactionbecomesspontaneous

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