Final answer:
Calculating the exact heat of vaporization of water at 298.2 K requires additional data on temperature-dependent enthalpy and entropy changes. The high heat of vaporization at the boiling point is due to hydrogen bonding. The heat of vaporization decreases at temperatures below the boiling point.
Step-by-step explanation:
The question is asking for the heat of vaporization of water at 298.2 K, considering that the known heat of vaporization at 373.2 K (the normal boiling point) is 40.66 kJ/mol.
Using the given specific heat capacities of water, one can calculate the amount of heat energy needed to raise the temperature of liquid water from 298.2 K to 373.2 K and then vaporize it. However, to provide the exact heat of vaporization at 298.2 K, one would typically need more data, such as the change in enthalpy and entropy of water at this specific temperature. Given that these values tend to vary with temperature, the assumption that the specific heat capacities are independent of temperature might not give an accurate result.
According to the data, the heat of vaporization of water is indeed very high due to the extensive hydrogen bonding between water molecules. This high energy requirement makes water an effective heat sink, absorbing substantial energy when transitioning from liquid to gas. It is also noted that the heat of vaporization decreases as the temperature decreases from the boiling point. But without explicit details of the dependence of these properties on temperature, we cannot calculate an exact new value for the heat of vaporization at 298.2 K.