NEET2017ChemistryThermodynamics (C)Actual
For a given reaction, Δ H = 35.5 k J m o l - 1 and Δ S = 83.6 J K - 1 m o l - 1 . The reaction is spontaneous at : (Assume that Δ H and Δ S do not vary with temperature)
Options
- AT < 425 K
- BT > 425 K
- CAll temperatures
- DT > 298 K
Correct answer
B. T > 425 K
Step-by-step solution
∵ Δ G = Δ H - T Δ S For a reaction to be spontaneous, Δ G = - v e i.e., Δ H < T Δ S ∴ T > Δ H Δ S = 35.5 × 10 3 J 83.6 J K - 1 i.e., T > 425 K