Exams › JEE Main › Chemistry
The effect of temperature on spontaneity of reactions are represented as: (A) ΔH +, ΔS −, Temperature any T, Spontaneity Non spontaneous (B) ΔH +, ΔS +, Temperature low T, Spontaneous (C) ΔH −, ΔS −, Temperature low T, Non spontaneous (D) ΔH −, ΔS +, Temperature any T, Spontaneous
- (1) (B) and (D) only
- (2) (A) and (D) only
- (3) (B) and (C) only
- (4) (A) and (C) only
Correct answer: (3) (B) and (C) only
Solution
Options (B) and (C) correctly describe the relationship between enthalpy (ΔH), entropy (ΔS), and temperature in determining spontaneity. In (B), a positive ΔH and positive ΔS at low temperatures can lead to spontaneity, while in (C), a negative ΔH and negative ΔS at low temperatures indicate non-spontaneity.
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