F.3 Chem. *勁人入！
1. Explain why changing a liquid to a gas requires a large amount of heat energy
2. Describe how the boiling point of water changes with pressure.
- PeterLv 71 decade agoFavorite Answer
1. It is because it requires a lot of energy for the molecules to spread out.
2. The higher the pressure is, the more difficult for the water molecule to jump out (vaporize). Thus it requires more energy (more heat) to vaporize. That leads to the increase of the boiling point.
- skwinwinLv 51 decade ago
1.As liquid needs extra heat energy to break the weak Van der Waal's force to turn to a gas.
2.When having a higher pressure, particles are more difficult to spread out,therefore it requires more heat energy to break the force between the molecules, so boiling point will increase.