What is the amount of heat absorbed by water when it evaporates at atmospheric pressure?

The amount of heat absorbed by water when it evaporates at atmospheric pressure is known as the latent heat of vaporization. For water, this value is approximately 2257 kJ/kg. This means that for every kilogram of water that evaporates, it absorbs 2257 kJ of heat energy, which is necessary to break the intermolecular forces holding the water molecules together in the liquid state.

Understanding the concept of latent heat is crucial in refrigeration and HVAC systems, as it underlines the energy transfer processes involved in phase changes. When water transitions from liquid to vapor, it absorbs significant amounts of heat, making it effective for cooling applications. This property is one of the reasons why water is often used in refrigeration systems, as it can absorb heat efficiently while changing its state.

The other values listed are not characteristic of the latent heat of vaporization for water at atmospheric pressure. Thus, the choice of 2257 kJ/kg accurately reflects the heat required for water evaporation under those conditions.