02.02: Sodium
Oh… this is going to be fun…!
As soon as I picked “Sodium”, I knew I wanted to demonstrate solvated electrons. I had only done that once before, and it was one of the coolest things I’d ever seen (no pun intended).
What didn’t make the video was my first attempt at the dry ice bath. I knew it had to cool down to less than -33 ºC, and I didn’t really want to use a whole bunch of acetone. I have gallons of 70% isopropyl alcohol, and I thought, there should be enough alcohol in the ratio to lower the freezing point of the little bit of water enough. Well, it did get to -34 ºC before the water froze around the test tube, thus preventing the inside of the test tube from getting any cooler than 0 ºC.
So, don’t try to make a dry ice-alcohol bath with diluted alcohol! Trust me!
By the time I figured out it wasn’t going to work, it was really late at night. I decided to finish in the morning, keeping in mind I had a limited time with the dry ice. When I went to bed, I had about 8 pounds of it left. When I started filming the next day, I had about 2 pounds. I had one shot, and thankfully, it worked. There were horrendous losses of ammonia in the apparatus, but I got enough to show the solvated electrons.
When I was done with that demo, I decided to film a little sodium and water reaction in the crystallizing dish as an opening scene. After two small pieces that just skipped around, I wanted some fire! I threw in a bigger piece, and it STILL just skipped around. Wanting more, I got a nice 1-liter Florence flask and a 250-mL beaker to cap it up. I threw in a big piece of sodium, cleaned of its mineral oil coating (which I didn’t do before) and thrown into distilled water (instead of tap).
It caught fire, alright, and as it danced around the surface of the water on fire, I started to cringe. I got further and further away (I was limited by a wall) because I knew it was generating more hydrogen than was burning off. Then it happened…
BANG!
The bottom of the beaker blew clean off before the rest of it even lifted off he flask, which, thankfully, survived intact. But boy, was that loud!
Several years ago, I did a similar experiment, and the results were even more spectacular. It it wasn’t winter, I would have recreated that experiment as well. That’s definitely an outside only one, and I’m not too sure my neighbors would like it much!
There is that, and a few other things I’d like to do with sodium. I have more than 200 grams of it, and I’m a little nervous because of how much pressure was in the small bottle. I need to open the big stock bottle, clean it up, and try some other experiments. But in the meantime, I’ll keep picking from the hat!
The next one won’t blow up, but should still be pretty colorful!
-Jason
