So lately I've been using ascorbic acid (very very tiny amounts) to neutralize the chlorine and chloramine in my tap water (temporary solution to improve flavor in lieu of a proper filter).
Just for fun, I decided to react a solution of ascorbic acid with some sodium bicarbonate in an attempt to make a sodium ascorbate solution. Then I got to thinking, how can I get the ascorbate out of the solution?
I figured boiling would do the trick, but for some reason, I thought that adding isopropyl alcohol to the solution might do something, maybe precipitate the crystals out? That probably sounds completely stupid, but forgive me, it's been years since I studied any kind of chemistry (and I wasn't planning on ingesting the solution, so I figured it couldn't hurt to try).
Anyway, the alcohol did nothing visible, so I figured I'd go ahead and book off the solution (figuring the alcohol would dissipate quickly with its low boiling temp).
All went well for some minutes, the alcohol seemed to have boiled off (the smell was gone), and the liquid level was going down so I expected to see some white precipitate forming after a while. Instead what happened surprised me, the solution started turning yellow, then darker as more water boiled off. I did eventually start seeing some cloudiness at the bottom which I assume was the sodium ascorbate, but I didn't boil all of the water off because the color intrigued me.
Any ideas what this could be? My first thought was some contamination, but the pan I used was washed and rinsed very thoroughly.
Some more details on the solution:
- about 1/2 teaspoon ascorbic acid
- about 1/4 teaspoon sodium bicarbonate
- mixed in roughly 2oz water and added a bit more sodium bicarbonate until everything stopped bubbling
- when the solution was completely clear and not bubbling, added about 1oz isopropyl alcohol (maybe less)
- boiled off about 2/3 of the solution
I eyeballed a lot of this and added stuff as I went (wasn't sure exactly how much ascorbic acid would dissolve) so those amounts may be quite a bit off, but the solution was crystal clear and not bubbling at all after I was done adding everything.
Hope someone with more knowledge than I can offer some insight!