Using enthalpies of formation (Appendix C), calculate ΔH° for the following reaction at 25°C. Also calculate ΔS° for this reaction from standard entropies at 25°C. Use these values to calculate ΔG° for the reaction at this temperature.
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- For the reaction NO(g)+NO2(g)N2O3(g) , use tabulated thermodynamic data to calculate H and S. Then use those values to answer the following questions. (a) Is this reaction spontaneous at 25°C? Explain your answer. (b) If the reaction is not spontaneous at 25°C, will it become spontaneous at higher temperatures or lower temperatures? (c) To show that your prediction is accurate, choose a temperature that corresponds to your prediction in part (b) and calculate G . (Assume that both enthalpy and entropy are independent of temperature.)arrow_forwardUse the data in Appendix G to calculate the standard entropy change for H2(g) + CuO(s) H2O() + Cu(s)arrow_forwardFor each of the following processes, identify the systemand the surroundings. Identify those processes that arespontaneous. For each spontaneous process, identify theconstraint that has been removed to enable the process to occur: Ammonium nitrate dissolves in water. Hydrogen and oxygen explode in a closed bomb. A rubber band is rapidly extended by a hangingweight. The gas in a chamber is slowly compressed by aweighted piston. A glass shatters on the floor.arrow_forward
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