Liquid nitrogen is a scientific staple that I’m sure we’re pretty much all familiar with. It’s a great demonstration of how the melting and boiling points can vary wildly and, of course, everyone loves shattering a frozen banana or two. However seeing the other stages of elemental gases is typically impossible as getting the required temperature is beyond the reach of most high school science labs. However there is a trick that we can use to, in essence, trick nitrogen into forming a solid: reducing the pressure to a near vacuum. The results of doing so are just incredible with the nitrogen behaving in some really peculiar ways:
The initial stages of the nitrogen transitioning into a solid is pretty standard with the reduced pressure resulting in the superheated boiling, plunging the temperature of the remaining liquid. The initial freezing is also something many will be familiar with as it closely mimics what happens when water freezes (although lacking water’s peculiar property of expanding when freezing). The sudden, and rather explosive, crystalline formation after that however took me by surprise as I’ve never really seen anything of that nature before. The closest thing I could think of was the fracturing of a Prince Rupert’s Drop although the propagation of the nitrogen crystalline structure seems to be an order of magnitude or two slower than that.
What really got me about this video is that it wasn’t done by a science channel or vlogger, it’s done by a bunch of chefs. Liquid nitrogen has been used in various culinary activities for over a century, mostly due to its extreme low temperatures which form much smaller ice crystals in the food that it chills. It should come as no surprise really as there’s been a huge surge in the science behind cooking with the field of molecular gastronomy taking off in recent decades. It just goes to show that interesting science can be done almost anywhere you care to look and its applications are likely far more wide reaching than you’d first think.