The table below shows standard entropies, S⊖S^\ominusS⊖.
| Substance | N2O4(g)\text{N}_2\text{O}_4(\text{g})N2O4(g) | NO2(g)\text{NO}_2(\text{g})NO2(g) |
|---|---|---|
| S⊖ / J mol−1K−1S^\ominus\text{ / J mol}^{-1}\text{K}^{-1}S⊖ / J mol−1K−1 | 304.3 | 240.1 |
What is the entropy change, ΔS⊖\Delta S^\ominusΔS⊖, in J mol−1K−1\text{J mol}^{-1}\text{K}^{-1}J mol−1K−1, for the following reaction?
N2O4(g)→2NO2(g) \text{N}_2\text{O}_4(\text{g}) \rightarrow 2\text{NO}_2(\text{g}) N2O4(g)→2NO2(g)−175.9-175.9−175.9
−64.2-64.2−64.2
+64.2+64.2+64.2
+175.9+175.9+175.9
24 exam-style questions on OCR A A Level Chemistry Enthalpy and entropy. Each one has a worked solution and a mark scheme showing where the marks go.