Monday, April 15, 2013

Water Balls

One day in Arizona, I made pancakes. The pans were a little different than I was used to; I normally use a buttered cast-iron skillet to fry my pancakes, but the apartment we were staying in didn't have any of those. As far as pans went, all they had were stainless steel frying pans - which are very different from cast-iron skillets.

When I was heating the pans for the pancakes, I couldn't tell how hot they were. I put my hand over one, but felt very little heat - probably because it didn't radiate much heat. So I left the pans to heat up more.

Finally I decided to try something else. I got my hands wet, so I could splash some water on one of the pans. If the water bubbled and boiled, that would mean the pan was hot. I splashed some water on. It didn't boil; instead, as it hit the pan, there was a dull clink, and the water turned into a bunch of tiny balls that rolled around on the pan, bouncing back and forth from one side to the other.

Now THAT was different. What was going on? I tilted the pan around, watching the balls bounce from one side to the other. When they hit each other, they merged into a larger ball that acted in a very similar way, but was flatter. I added more water, with the same results. When the balls had all merged into a big blob, I threw it into the air and caught it again. When it hit the pan, it broke into a bunch of tiny balls that bounced around some more. It was very entertaining.

Finally I forgot about it, and went back to my pancakes. I took a slice of butter and put it on the pan. Instantly, white smoke poured up - the butter was burning! I foolishly threw a ladle-full of batter onto the butter, to cool things down and stop the smoke. BAD idea; I just got more smoke.

This is what was going on: The pan was hot – very hot. When I put the water on the pan, the heat was so intense that the water began to evaporate before it even touched the pan. The blast of water vapor from the evaporation was so strong that it held the water droplet up - it was literally floating on a cushion of hot air. The water turned into balls due to surface tension, and bounced around because there was nothing to disturb their sideways motions.

Yesterday I tried the water-balls trick again, except with a saucepan instead of a frying pan. This time I heated it on high heat, and left it for a while before playing with it. I got the same wonderful results. You can see photos of the experiment throughout this post. If you try making water balls yourself, be careful; some pans can be damaged by high temperatures.

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