Ice is wet on its surface due to a phenomenon called surface melting.
Understanding Surface Melting
British scientist Michael Faraday observed this phenomenon over 150 years ago. He noted that even below freezing temperatures, a thin layer of water exists on the surface of ice. This layer is what makes ice feel wet.
Why Doesn't the Surface Water Freeze?
The question of why this surface water doesn't freeze in sub-zero environments has been a subject of scientific inquiry. Several factors contribute to this:
- Pressure: Pressure can lower the melting point of ice.
- Surface imperfections: Irregularities on the ice surface can promote melting.
- Ion concentration: Dissolved ions present on the surface also act to depress the freezing point of the water film.
Wetness Explained
Wetness is generally defined as the presence of a liquid on a surface. Since ice has a liquid layer on its surface, it can be considered wet.
Conclusion
While solid, ice exhibits a thin layer of liquid water on its surface, making it wet to the touch.
