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What is the standard enthalpy change for the phase transition reaction of water from ice to liquid at 25°C and 1 atm pressure?

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To calculate the standard enthalpy change for the phase transition of water from ice to liquid at 25C and 1 atm pressure, we need to consider two steps: 1. Heating the ice from -273.15C  0 K  to 0C  273.15 K 2. Melting the ice at 0C  273.15 K Step 1: Heating the ice from -273.15C to 0CThe heat capacity of ice is approximately 2.09 J/gK. To calculate the enthalpy change for heating the ice, we can use the formula:H = m  C  Twhere H is the enthalpy change, m is the mass of the substance, C is the heat capacity, and T is the temperature change.Assuming 1 mole of ice  18.015 g , the enthalpy change for heating the ice is:H1 =  18.015 g    2.09 J/gK    273.15 K - 0 K  = 18.015 g  2.09 J/gK  273.15 K  10,340 JStep 2: Melting the ice at 0CThe enthalpy of fusion for water  melting ice to liquid  is 6.01 kJ/mol.H2 = 6.01 kJ/mol  1000 J/kJ = 6010 JNow, we can add the enthalpy changes for both steps to find the total enthalpy change for the phase transition of water from ice to liquid at 25C and 1 atm pressure:H_total = H1 + H2 = 10,340 J + 6010 J  16,350 JTherefore, the standard enthalpy change for the phase transition of water from ice to liquid at 25C and 1 atm pressure is approximately 16,350 J/mol.

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