The freezing point is the temperature at which a liquid turns into a solid. For most substances, this occurs when the temperature drops to a specific value, allowing the molecules to slow down and arrange themselves into a solid structure. For example, the freezing point of water is 0°C or 32°F. Different substances have different freezing points. For instance, ethanol freezes at about -114°C or -173°F, while mercury freezes at -39°C or -38°F. The freezing point can also change under pressure, which is why ice can form at temperatures above 0°C in certain conditions.