Final answer:
To calculate the standard entropy change of a reaction, one must subtract the standard entropies of the reactants from those of the products. Standard entropy values are needed to perform this calculation, which represents the disorder in the system. Without specific data on reactants and products, we cannot calculate the change in entropy.
Step-by-step explanation:
To calculate the standard entropy change (ΔS°rxn) of a reaction at 25.0 °C, we utilize standard entropies (S°) which are absolute entropy values for substances at a pressure of 1 bar and a temperature of 298.15 K. The standard entropy change for the reaction is calculated by subtracting the sum of the standard entropies of the reactants from the sum of the standard entropies of the products, while taking into account their stoichiometric coefficients in the balanced equation.
Using the formula ΔS° = ΣvS°(products) – ΣvS(reactants), where v represents the stoichiometric coefficients, we would look up the standard entropies for each reactant and product in the provided appendices or tables in textbooks. However, for this exercise, we are not given specific reactants, products, or their entropies. Instead, we need data for actual compounds to perform this calculation.
It's important to note that if a reaction releases heat and proceeds to equilibrium in a bomb calorimeter with a ΔH = -750 kcal/mol, indicating an exothermic reaction. Furthermore, an absolute value for the entropy change can be |AS| = 116.2 cal/mol-deg. This shows whether there is an increase or decrease in disorder in the system. Entropy generally increases when a system goes from a more ordered to a more disordered state.