JEE Main 2026 Chemistry question
Consider the following data for the reaction X₂(g)+Y₂(g)⇌2XY(g) at 600 K.
| Compound | ΔfH°₆₀₀K (kJ mol⁻¹) | S°₆₀₀K (J mol⁻¹K⁻¹) | |---|---|---| | XY(g) | 42 | 200 | | X₂(g) | 8 | 140 | | Y₂(g) | 80 | 250 |
The ΔrG° (in kJ mol⁻¹) for the reaction is:
Answer: (B)
Solution
ΔrH°=2(42)−8−80=−4 kJ/mol. ΔrS°=2(200)−140−250=10 J/(mol K)=0.01 kJ/(mol K). ΔrG°=−4−600(0.01)=−10 kJ/mol.