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)

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).<br /><br />Since the temperature remains constant during the phase change, we can calculate the total thermal energy (q) required using the following formula:<br /><br />q = n * ΔH_vap<br /><br />where:<br /><br />* q is the thermal energy<br />* n is the number of moles<br />* ΔH_vap is the molar heat of vaporization<br /><br />Substituting the given values:<br /><br />q = 15.0 mol * 40.8 kJ/mol <br />q = 612 kJ<br /><br />Therefore, the amount of thermal energy required is **612 kJ**.<br />