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Two methods of making ethyl ethanoate are compared using the Eco-Scale. The penalty points are given in the table. Method 1: ethanoic acid reacts with ethanol, with concentrated sulfuric acid as the catalyst. The mixture is heated in a microwave reactor for 40…
Which species are present after 14 dm3 of ethyne has reacted with 20 dm3 of hydrogen to produce ethane? All gas volumes are measured at the same temperature and pressure. C2H2(g) + 2 H2(g) → C2H6(g) A. 14 dm3 of…
Deduce the expression for Kc of this reaction.
Predict, with a reason, the effect of increasing the total pressure, at constant temperature, on the position of equilibrium.
Explain why a higher temperature speeds up this reaction, with the help of annotations that you add to the Maxwell-Boltzmann distribution below, which is drawn for a temperature T1.
The Maxwell-Boltzmann distribution for the uncatalysed reaction at temperature T1 is shown below. Add annotations to show how a catalyst changes the situation.
The reaction takes place on the surface of a nickel catalyst. The following mechanism is proposed, in which Ni-C represents carbon atoms bonded to the nickel surface: CH4 + Ni → Ni−C + 2 H2 (slow) Ni−C + CO2 → Ni−CO + CO (fast)…
Use section 13 of the data booklet and the standard molar entropy of hydrogen, S⊖(H2(g)) = +130.7 J K−1 mol−1, to calculate ΔS⊖ for the forward reaction, in J K−1.
At 1200 K, calculate ΔG⊖ for the forward reaction and the value of the equilibrium constant, K. Use sections 1 and 2 of the data booklet. If you were unable to obtain an answer for 3f, use 230 J K−1, but this is not the correct…
Determine the minimum temperature, in K, at which the forward reaction is spontaneous. Use section 1 of the data booklet. If you were unable to obtain an answer for 3f, use 230 J K−1, but this is not the correct value.