How to Create Plasma in Your Microwave

The microwave oven has inspired a wide variety of home experiments... which usually end with something catching fire. Optical discs, metal melting, exploding eggs and sausages, and the occasional idiot YouTuber who puts it on his head set the pace, but today we have something more classic: Plasma. The traditional method to create plasma in your microwave is fire; however, a safer (and much less spectacular) alternative is to use a grape. Yes, you read that right.

Are you bored? Looking for a weekend project? Is there a spare microwave in the house that you could sacrifice to the dark gods of science? If the answer to these three questions is yes and the risk of fire doesn't intimidate you, then you should learn how to create plasma in your microwave. The most common way involves a little fire (a match or a bunch of incense), and something to cover the flame (a glass or jar that doesn't absorb too much energy). You light it, cover it, close the microwave, press Start, and the rest is enjoying the show. But there's another variant... one that doesn't even need fire. The first step is a trip to the market.

Plasma in the Microwave... with Grapes?

Yes, it's a grape cut almost all the way through, joined by a tiny piece of skin. An old video from the popular Veritasium channel not only demonstrates it but explains some of the science behind it. In relaxed terms, if we inject enough energy into a gas, we cause the molecules to lose electrons, and the mixture or "soup" of negative electrons and positive molecules gives us plasma. One of the keys in this particular example is the amount of grape available. The energy concentrated in such a small spot creates a magnetic field, and the flow of ions goes from one half of the grape to the other. At first, that happens through the skin, but eventually it ends up "jumping" through the air. That jump ionizes the gas around it, and the result is the burst of plasma we see in the short. With slight adjustments to the skin and an additional reduction in the grape's mass (as well as its moisture), the effect is even more spectacular.

So... is it something exclusive to grapes? The answer is no. In the video they explore the possibility of making "artificial grapes" with small pieces of cotton soaked in conductive liquid (read electrolyte), say a grape extract, or saltwater. Other options? Reports talk about spinach, cabbage, and various kinds of beans. Remember: Plasma can destroy your microwave and cause a lot of damage. Be careful.

Source: Vox