Oliver and I watch fireworks over the Potomac, 2010So how was the fireworks show you saw last night? Because we live in a tall building, we went to the roof (our celebration was low-key this year) and got to enjoy at least 9 different firework shows, including the one downtown. We could see the Washington Memorial all lit up, it was fantastic really.
So what gives fireworks their color? The answer is metal salts. In chemistry terms, salts are compounds created from the reaction of an acid and a base (table salt is sodium (Na from a base), chloride (Cl from an acid), NaCl). Different salts give off different colors. See the chart I found here below.
| Color | Compound |
| Red | strontium salts, lithium salts lithium carbonate, Li2CO3 = red strontium carbonate, SrCO3 = bright red |
| Orange | calcium salts calcium chloride, CaCl2 calcium sulfate, CaSO4·xH2O, where x = 0,2,3,5 |
| Gold | incandescence of iron (with carbon), charcoal, or lampblack |
| Yellow | sodium compounds sodium nitrate, NaNO3 cryolite, Na3AlF6 |
| Electric White | white-hot metal, such as magnesium or aluminum barium oxide, BaO |
| Green | barium compounds + chlorine producer barium chloride, BaCl+ = bright green |
| Blue | copper compounds + chlorine producer copper acetoarsenite (Paris Green), Cu3As2O3Cu(C2H3O2)2 = blue copper (I) chloride, CuCl = turquoise blue |
| Purple | mixture of strontium (red) and copper (blue) compounds |
| Silver | burning aluminum, titanium, or magnesium powder or flakes |
So there you have it, the presence of barium makes green, copper makes blue, strontium makes red. And when you mix copper and strontium salts together, you've got purple. Pretty cool.
And if you didn't get your firework fix from yesterday, take a look at this interesting NOVA video concerning the color of fireworks. It's interesting stuff.
2 comments:
being the color nerd that i am, i loved this post. i really liked seeing the different compounds. it felt like science.
So, so cool. I'm so glad you posted this, because I was wondering about this very thing. I can only seem to remember that magnesium burns white, and then I forget the rest. Thanks, my chemistry go-to gal.
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