The Leidenfrost effect is when a liquid, like water, touches a surface that is much hotter than its boiling point and instantly forms a thin vapor layer underneath it. That vapor layer acts like a cushion, so the droplet can skitter, dance, or float instead of boiling away immediately.

How it works

  • The hot surface vaporizes the bottom of the liquid first.
  • The vapor layer reduces direct contact with the surface.
  • With less contact, heat transfers more slowly, so evaporation is delayed.

What you might see

  • Water droplets “dance” across a very hot pan.
  • Drops may last longer than expected on the surface.
  • This usually happens only above a specific temperature called the Leidenfrost point.

Why it matters

  • In cooking, it can help explain why water behaves oddly on a screaming-hot pan.
  • In industry, engineers study it because it affects boiling, cooling, and heat transfer on extreme surfaces.

TL;DR: the Leidenfrost effect is a vapor-cushion phenomenon that makes droplets hover and evaporate more slowly on very hot surfaces.