How much heat (in kJ) is absorbed when 24.8 g #H_2O(l)# at 100°C and 101.3 kPa is converted to steam at 100°C?
In this case, the water is already at it's boiling point at the indicated pressure, so the only energy adsorption required is the heat of vaporization. That is 2257 J/g for water (it is different for every compound).
24.8g * 2257 J/g = 55973.6 J or 55.974 kJ
With the data precision limitation of 24.8g being three significant figures, this answer would most practically be stated at 55.97 kJ