If the pressure is low enough, the boiling point and the melting point of water can be equal. What is this point called? Do you think this point can exist for substances other than water? Explain your reasoning.
This is called "evaporation" when a liquid is boiling hot, it starts to evaporate. That is how clouds form! Every liquid is able to evaporate because when it's heated up, it turns into gas. That gas is vapor.
