Science!, Science! For Parties

Science! For Parties!: The Leidenfrost Effect

Ever been on a date and wanted to bust out the double whammy of impressing your dinner companion with your cooking skills and your science knowledge? Then you’re in luck because today’s Science! For Parties! is going to teach you how to do just that. As always don’t try this at home without a sober adult present.

Take whatever pan you feel like it and place it on you stove. Turn the stove on high and let the pan heat up. You’ll want to give it at least a few minutes as the cooking surface of the pan will need to be at a minimum of 212 Degrees Fahrenheit (100 Degrees Celsius). When it’s ready fill up a cup or baster with water. A baster is better but not necessary. Take the water and pour a little bit into the pan. If the pan is hot enough then instead of sizzling and evaporating the water will bead together and float on the skillet like a disc on an air hockey table.

It’s a pretty cool effect but it’s even more impressive when you marvel your guest with the scientific principle behind it. When a surface area has been heated at a certain point well beyond a liquid’s boiling point when that liquid is poured onto the surface the liquid will evaporate so fast that it creates a layer of vapor that cushions the remaining liquid and keeps it from coming into direct contact with the surface. This is called the Leidenfrost Effect, named after Johann Gottlob Leidenfrost who first wrote about it in his 1756 work A Tract About Some Qualities of Common Water.

The point needed to achieve the Leidenfrost Effect varies from liquid to liquid according to each of their respective boiling points. If you’re a math nerd there are some cool equations to get into here with the heat coefficient and the pressure field created by the vapor layer but let’s be real I’m not gonna get into all that in a blog post about neat science tricks. What I will tell you however is that this same principle has allowed people to (briefly) stick their wet hand into molten lead without harm and burp out liquid nitrogen. Both of which are cool but you should not even consider trying unless you’ve got a PhD in one of the physical sciences and even then don’t be an idiot dude.

Anyway that wraps it up here at Science! For Parties! Below are some YouTube clips demonstrating the Leidenfrost effect. Hopefully your dinner date will be so impressed with your big brain they ask you if they can have desert before you cook dinner. If you know what I’m saying… ahuminahumina… Science is Sexy.

Links:

https://www.youtube.com/watch?v=qwfzqMVJUok

https://www.youtube.com/watch?v=mZenCYF1IpM