Exams › JEE Main › Chemistry
Consider these two reactions: A + B → C + D, with ΔG° = +x kJ D + E → F, with ΔG° = −y kJ For the overall reaction A + B + E → C + F to be spontaneous, which statement is correct?
- 2x = y
- x > y
- x < y
- x = y × TΔS
Correct answer: x > y
Solution
For the overall reaction to be spontaneous, the total change in Gibbs free energy (ΔG) must be negative. Since the first reaction has a positive ΔG and the second has a negative ΔG, the magnitude of the positive ΔG from the first reaction must be less than the negative ΔG from the second reaction, leading to the conclusion that x must be greater than y.
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