When a liquid drop is placed on a surface held at a temperature
much higher than the liquid’s boiling point (such as
a drop of water in a very hot pan) it hovers on its own vapor
cushion, without wetting the surface. This phenomenon is called
film-boiling and occurs beyond a surface temperature called
the Leidenfrost point (about 200 - 300 ºC for water on
flat surfaces, depending on surface quality).
