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What is the standard enthalpy change for the phase transition reaction of water when it freezes at a temperature of -10°C and a pressure of 1 atm?

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The standard enthalpy change for the phase transition of water when it freezes is called the enthalpy of fusion. The enthalpy of fusion for water is 6.01 kJ/mol at 0C and 1 atm pressure. However, you are asking for the enthalpy change at -10C and 1 atm pressure.To determine the enthalpy change at -10C, we can use the heat capacity of ice and water to calculate the additional energy required to cool the water from 0C to -10C before freezing. The heat capacity of ice is approximately 2.09 J/gK, and the heat capacity of water is approximately 4.18 J/gK. The molar mass of water is 18.015 g/mol.First, we need to calculate the energy required to cool the water from 0C to -10C:q_water =  4.18 J/gK    10 K    18.015 g/mol  = 782.99 J/molNext, we need to calculate the energy required to cool the ice from 0C to -10C:q_ice =  2.09 J/gK    10 K    18.015 g/mol  = 376.52 J/molNow, we can find the total enthalpy change for the phase transition at -10C:H_total = H_fusion + q_water + q_iceH_total = 6.01 kJ/mol + 0.78299 kJ/mol + 0.37652 kJ/molH_total  7.17 kJ/molSo, the standard enthalpy change for the phase transition reaction of water when it freezes at a temperature of -10C and a pressure of 1 atm is approximately 7.17 kJ/mol.

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