Phenomena

Leidenfrost Atop Gasoline

The animations above show a little of what happens when you pour a spoonful of liquid nitrogen onto a container of gasoline. A couple of things are happening simultaneously here. First of all, the liquid nitrogen is experiencing the Leidenfrost effect. Because of the extreme difference in temperature between the gasoline (~20 degrees C) and the liquid nitrogen (-196 degrees C), part of the nitrogen is evaporating immediately, creating a vapor layer that insulates the remainder of the liquid nitrogen and allows it to float above the gasoline surface. The same thing happens to water drops on a very hot skillet.

The extreme cold of the nitrogen also seems to have formed some ice that’s further protecting the nitrogen drop. I’m not 100% sure what that would be made of, though – a mixture of water and gasoline?

Finally, there’s the simultaneous evaporation of the liquid nitrogen and the sublimation of the ice. This is the white vapor we see propelling and spinning the ice/drop. Note the “bounce” that happens in the top animation. The drop never actually impacts the wall. When it gets close, the escaping vapors are affected by the wall and start pushing the drop in a new direction! Check out the whole video below. (Image credit: carsandwater; via Gizmodo)

Leave a Reply

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.

%d bloggers like this: