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Sure. What is the standard enthalpy change for the reaction of mixing 10g of ethyl alcohol (C2H5OH) with 25g of water (H2O) at 25°C, given that the heat evolved is 12.5 kJ?

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To calculate the standard enthalpy change for the reaction, we need to determine the moles of each substance and then use the heat evolved  q  to find the enthalpy change per mole.First, let's find the moles of each substance:Molar mass of ethyl alcohol  C2H5OH  = 2 12.01  + 6 1.01  + 1 16.00  = 46.07 g/molMoles of ethyl alcohol = mass / molar mass = 10 g / 46.07 g/mol = 0.217 molMolar mass of water  H2O  = 2 1.01  + 1 16.00  = 18.02 g/molMoles of water = mass / molar mass = 25 g / 18.02 g/mol = 1.387 molNow, we can use the heat evolved  q  to find the enthalpy change per mole. Since the heat evolved is 12.5 kJ, the enthalpy change for the reaction is -12.5 kJ  exothermic reaction .To find the enthalpy change per mole, we need to divide the total enthalpy change by the total moles of reactants:Total moles = moles of ethyl alcohol + moles of water = 0.217 mol + 1.387 mol = 1.604 molEnthalpy change per mole = total enthalpy change / total moles = -12.5 kJ / 1.604 mol = -7.79 kJ/molThe standard enthalpy change for the reaction of mixing 10g of ethyl alcohol with 25g of water at 25C is -7.79 kJ/mol.

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