Weird Science

After my rocket candy post, I continued to experiment with various oxidizers and fuels and ratios. More on that later, but I learned something more about the rocket candy reaction.

I tested 26% sucrose and 74% saltpeter in powdered form with a magnesium ribbon for ignition. One reason for the ribbon is that my blow torch would have blown the powder away. In case you don't know, magnesium burns very hot and bright with the reaction:

2Mg + O2 -> 2MgO

It is sort of the ultimate fuse, and was used to make incendiary bombs in WWII. Now that I have a roll of such ribbon, it will be my new method for safety reasons and improved odds of successful ignition.

Anyway, the reaction went off just fine with no excess fuel (in the form of smoke and carbon deposits). I think that rocketeers like the smoke; it makes a nicer display when launching the vehicle and aids faraway viewing as the rocket climbs. For my purposes, the smoke and carbon deposits are a nuisance and also waste good sugar.

Since I had no carbon left over, I had a very good look at the solid product of this reaction, shown here in a melted aluminum container. By the way, the black carbon deposits inside the "O" and above the melted product were from another test, so you can see the very clear difference of the purer burn. 

Note what a pure white the K2CO3 is. Additionally, it felt like hard smooth plastic and was a bit hard to pry up. I kept a few pieces for whatever reason, but that is where my discovery came in. After an hour of so in my home, it felt a bit wet and tacky (such that I had to wash my hands). This intrigued me since it had been hard and dry not much earlier.

I looked up potassium carbonate on wikipedia and learned a new word. The compound is deliquescent. I had no idea what that meant, and was pretty sure it doesn't mean that it tastes good on a sandwich. It means this material will take hydrogen and oxygen from the environment (as available in the form of humidity) to the point of not just hydrating itself but actually forming an aqueous solution and dissolving itself. At that point I threw it away, thinking it would start making a mess. Maybe I should have put it in a tub in the garage and watched over time. I had no idea such weird things exist!

Oh brave new world that has such compounds in't!

Thanks for reading,

Paul