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A chemical reaction was carried out at constant temperature and pressure. The initial concentration of the reactants and products were known. After a certain amount of time, the concentration of the reactants and products were measured. Using non-equilibrium thermodynamics, calculate the magnitude and sign of the entropy change of the system during the reaction.

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To calculate the entropy change of the system during the reaction, we can use the following equation:S = nR * ln C_final/C_initial where S is the entropy change, n is the number of moles of the substance, R is the gas constant  8.314 J/molK , C_initial is the initial concentration, and C_final is the final concentration.First, we need to determine the number of moles of each reactant and product involved in the reaction. This can be done using the stoichiometry of the reaction and the initial and final concentrations. Let's assume the reaction is as follows:aA + bB  cC + dDwhere A and B are reactants, C and D are products, and a, b, c, and d are their respective stoichiometric coefficients.Next, we need to calculate the change in the number of moles for each reactant and product:n_A = n_A_initial - n_A_finaln_B = n_B_initial - n_B_finaln_C = n_C_final - n_C_initialn_D = n_D_final - n_D_initialNow, we can calculate the entropy change for each reactant and product:S_A = n_A * R * ln C_A_final/C_A_initial S_B = n_B * R * ln C_B_final/C_B_initial S_C = n_C * R * ln C_C_final/C_C_initial S_D = n_D * R * ln C_D_final/C_D_initial Finally, we can find the total entropy change of the system by summing the entropy changes of each reactant and product:S_total = S_A + S_B + S_C + S_DThe sign of the entropy change will depend on the values of the initial and final concentrations. If the final concentration is greater than the initial concentration for a reactant or product, the entropy change will be positive. If the final concentration is less than the initial concentration, the entropy change will be negative.

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