Two processes are investigated in an insulated calorimeter at 25 °C.
Process X: C12H22O11(s) → C12H22O11(aq) ΔH = +5.4 kJ·mol⁻¹
Process Y: C12H22O11(aq) + 12 O2(g) → 12 CO2(g) + 11 H2O(l) ΔH = −5640 kJ·mol⁻¹
A solution initially contains 0.0500 mol of sucrose (C12H22O11) dissolved in water. Pure oxygen is bubbled into the solution, and a biocatalyst initiates Process Y. Assume the calorimeter has negligible heat capacity and that the combined mass of solution and products is 250 g with a specific heat capacity of 4.18 J·g⁻¹·°C⁻¹.
(a) Classify Process X and Process Y individually as physical or chemical changes, citing evidence from the equations.
(b) Calculate the expected temperature change of the calorimeter contents if only Process X occurs for the initial 0.0500 mol of sucrose. Show your work.
(c) Calculate the expected temperature change if Process Y proceeds to completion for the same amount of sucrose. (Assume Process X is negligible under these conditions.)
(d) Compare the magnitudes of the temperature changes calculated in parts (b) and (c), and explain how these results are consistent with your classifications in part (a).
(e) Discuss whether the overall transformation from solid sucrose to gaseous CO2 and liquid H2O can be considered reversible under laboratory conditions, providing chemical reasoning.