Playing around with sparklers on new year and the day after brought about this experiment.
Material
erlenmeyer flask, mortar, filter paper, funnel, spent sparklers, destilled water
Caution
barium hydroxide is corrosive, wear safety goggles
Experimental
Some freshly spent sparklers are ground in a mortar. Water is added and the resulting slurry is filtered to give a clear colorless solution of barium
hydroxide. The solution can be used as is for a gas test of carbon dioxide. If carbon dioxide is present the solution will turn clowdy.
Explanation
Sparklers contain barium nitrate. On burning it decomposes to barium oxide, nitrogen and oxygen.
2 Ba(NO3)2 --> 2 BaO + N2 + 5 O2
Barium oxide remains in the ashes and reacts with water to barium hydroxide. The barium hydroxide can be extracted with water.
BaO + H2O --> Ba(OH)2
Pictures
Grindig spent sparklers and adding water: the slurry is strongly alkaline.
Filtering and the resulting barium hydroxide solution.
Ay man but dude there's a lot of other stuff too.... The kind I know of would get you some Mg(OH)2 as well j_sum1 - 19-1-2015 at 16:40
Don't barium compounds show a pale apple green in flame tests? On this basis, I rather suspect that there is more Mg than Ba in the
sparklers I have encountered.
And as for the gas test with CO2, won't all group two hydroxides behave in the same way?
[disclaimer]
I have not actually looked up the composition of sparklers. I like this idea though. Sounds like fun.nezza - 20-1-2015 at 01:12
To get a decent green from Barium you need a chlorine donor in the mix. Barium nitrate alone does not give much colour to pyrotechnic mixes.Doktor Klawonn - 20-1-2015 at 11:20
Afaik there is no magnesium in the sparklers, but aluminum and iron. And then Mg(OH)2 is not really soluble in water so it would remain in
the filter.Artemus Gordon - 20-1-2015 at 12:56
And as for the gas test with CO2, won't all group two hydroxides behave in the same way?
I would recommend calcium hydroxide for CO2 tests, so you don't have toxic Barium to dispose of.
If you have a mexican supermarket nearby, go to the spices section and buy a package of "Cal". This is food grade Ca(OH)2, used to turn
dried corn into hominy. You can also go to any building supply store and buy builder's lime, but who wants 50 lbs. of the stuff. Supposedly garden
lime can also be Ca(OH)2, but all I have ever seen is calcium carbonate.
