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The Amount of Thermal Energy Is __ KJ in Order to Change 15.0 Mol of Water at 100 Degrees Celcius from Liquid to Vapour, Without Any

Question

The amount of thermal energy is __ kJ in order to change 15.0 mol of water at 100 degrees celcius from liquid to vapour, without any change in temperature. (refer to data sheet, pay attention to significant digits)

Solution

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Answer

The heat required to change a substance from liquid to vapor at its boiling point is called the heat of vaporization. The heat of vaporization of water is 40.8 kJ/mol (refer to a standard data sheet for this value).Since the temperature remains constant during the phase change, we can calculate the total thermal energy (q) required using the following formula:q = n * ΔHvapwhere:* q is the thermal energy* n is the number of moles* ΔHvap is the molar heat of vaporizationSubstituting the given values:q = 15.0 mol * 40.8 kJ/mol q = 612 kJTherefore, the amount of thermal energy required is **612 kJ**.