Pirotecnia Posted May 31, 2012 Share Posted May 31, 2012 Hello, I "think" i've made some boric acid by mixing a solution of sodium borate (borax) with HCL and recovered the white precipitate.Do you know some way of test if the product i've made it's really boric acid? Thanks! Link to comment Share on other sites More sharing options...
Peret Posted June 1, 2012 Share Posted June 1, 2012 Taste it. Chances are it's salt. Link to comment Share on other sites More sharing options...
Mumbles Posted June 1, 2012 Share Posted June 1, 2012 If you did it right, it should be primarily boric acid actually. There aren't really good at home tests for boric acid. You could try dissolving some in alcohol, and burning that to ensure you get a green flame. Any trace of sodium would completely over power it though. Link to comment Share on other sites More sharing options...
Pirotecnia Posted June 1, 2012 Author Share Posted June 1, 2012 If you did it right, it should be primarily boric acid actually. There aren't really good at home tests for boric acid. You could try dissolving some in alcohol, and burning that to ensure you get a green flame. Any trace of sodium would completely over power it though. Thanks!! I've made the test of green flame and this is the result: It's really boric acid! I think.. Link to comment Share on other sites More sharing options...
Mumbles Posted June 1, 2012 Share Posted June 1, 2012 Looks pretty good to me. I can't tell if that yellowish tinge on the right side of the image is from sodium or the camera. If you recall it being green all around in person, you're probably good to go, especially if just to protect aluminum. If it was really there, washing with some cold water should hopefully get rid of it all. There is honestly much less sodium that I would have expected. Link to comment Share on other sites More sharing options...
psyco_1322 Posted June 2, 2012 Share Posted June 2, 2012 Usually pics of green burning alcohol look like there is light spots like that. I have several pics and they look similar. You get random orange flips in the flames from impurities, dirt, stuff in the air. A pinch of salt in methanol makes a nice yellow-orange flame. I'd like to mention you can get a pound or so as roach killer for about $3-5 at the store. Its about 99% boric acid. There are also USP grades at most pharmacies. You would use sodium bicarbonate if you wanted to produce some sodium chloride. Link to comment Share on other sites More sharing options...
warywolfen Posted June 3, 2012 Share Posted June 3, 2012 Taste it. Chances are it's salt. Don't taste it, H3BO3 is toxic. The standard test is to mix it with a little methanol, then add a drop or two of HCl or H2SO4. This creates the ester (CH3)3BO3, which when ignited, burns with a green flame. The strong acid is necessary, to protonate the H3BO3 and create the electrophile which attacks the O of the methanol. Without the strong acid, some ester will form, but it will exist in equilibrium with the alcohol & boric acid, and the green flame won't be nearly as intense. Link to comment Share on other sites More sharing options...
Peret Posted June 3, 2012 Share Posted June 3, 2012 A taste wouldn't hurt you. Welcome to the forum, warywolfen. Socorro is a small town, if that's your real picture I wonder if we may have met. Are you associated with the university? Link to comment Share on other sites More sharing options...
warywolfen Posted June 3, 2012 Share Posted June 3, 2012 I got a little ahead of myself, there. Actually that test will give a green flame with borates, generally, not just H3BO3. Sodium borate is basic. So, dissolve some of what you think is boric acid in water, and test the sol'n with pH paper (or a pH meter, if you have one). If it's basic, there's sodium borate present. If it's slightly acidic, it's boric acid. H3BO3 is a very weak acid, but it is an acid. Link to comment Share on other sites More sharing options...
psyco_1322 Posted June 9, 2012 Share Posted June 9, 2012 Don't taste it, H3BO3 is toxic.... Yeah, don't eat half a pound of it, you might die....or salt. Link to comment Share on other sites More sharing options...
Recommended Posts