Exams › JEE Main › Chemistry
The standard reaction Gibbs energy for a chemical reaction at an absolute temperature T is given by ΔG° = A − BT where A and B are non-zero constants. Which of the following is TRUE about this reaction? (1) Exothermic if B < 0 (2) Endothermic if A > 0 (3) Exothermic if A > 0 and B < 0 (4) Endothermic if A < 0 and B > 0
- Exothermic if B < 0
- Endothermic if A > 0
- Exothermic if A > 0 and B < 0
- Endothermic if A < 0 and B > 0
Correct answer: Exothermic if A > 0 and B < 0
Solution
The correct option indicates that the reaction is exothermic when the standard reaction Gibbs energy decreases with increasing temperature, which occurs when A is positive and B is negative. This implies that the reaction releases energy as heat, characteristic of exothermic processes.
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