The table below shows standard entropies, S⊖S^\ominusS⊖.
| Substance | N2(g)\text{N}_2(\text{g})N2(g) | H2(g)\text{H}_2(\text{g})H2(g) | NH3(g)\text{NH}_3(\text{g})NH3(g) |
|---|---|---|---|
| S⊖ / J K−1 mol−1S^\ominus\text{ / J K}^{-1}\text{ mol}^{-1}S⊖ / J K−1 mol−1 | 192 | 130 | 193 |
What is the standard entropy change, ΔS⊖\Delta S^\ominusΔS⊖, in J K−1 mol−1\text{J K}^{-1}\text{ mol}^{-1}J K−1 mol−1, for the formation of 1 mol of NH3(g)\text{NH}_3(\text{g})NH3(g) from its constituent elements in their standard states?
−196-196−196
−98-98−98
+98+98+98
+196+196+196
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.