7/11/2019 CHEM21_AS_Authentic_Reading - Google Docs NAME DATE CLASS INVESTIGATIVE PHENOMENON Firework Colors Chemistry by Anne Helmenstine Fireworks colors are a matter of chemistry. The colors come partly from the elements and compounds used in fireworks and partly by incandescence or light produced by different temperatures. Here’s a look at how fireworks colors work: Firework Colors – Luminescence of Element and Compounds When chemicals are heated, the ions emit characteristic wavelengths or colors of light. This works much like the flame test, a method used to identify a substance by its color in a flame. Metal ions are responsible for common colors: Color Red Orange Gold Compound strontium salts, lithium salts lithium carbonate, Li2CO3 = red strontium carbonate, SrCO3 = bright red calcium salts calcium chloride, CaCl2 calcium sulfate, CaSO4∙xH2O, where x = 0,2,3,5 incandescence of iron (with carbon), charcoal, or lampblack Copyright © Savvas Learning Company LLC. All Rights Reserved. Savvas is not responsible for any modifications made by end users to the content posted in its original format. https://docs.google.com/document/d/1fPnBYBxG3HxUOutVq3BLdszgaZA4x3ZcVSYb420LrZ4/edit# 1/3 7/11/2019 CHEM21_AS_Authentic_Reading - Google Docs NAME DATE Color Yellow Electric white Green Blue CLASS Compound sodium compounds sodium nitrate, NaNO3 cryolite, Na3AlF6 white­hot metal, such as magnesium or aluminum barium oxide, BaO barium compounds + chlorine producer barium chloride, BaCl+ is bright green copper compounds + chlorine producer copper acetoarsenite (Paris Green), Cu3As2O3Cu(C2H3O2)2 = blue copper (I) chloride, CuCl = turquoise blue mixture of strontium (red) and copper (blue) compounds Purple burning aluminum, titanium, or magnesium powder or flakes Silver Quality control is important in all aspects of fireworks design, including color formulation. Impurities and contaminants in the chemicals can completely ruin the effect. For example, even trace amounts of sodium in a chemical mixture will produce a bright yellow color that can drown out weaker colors. Firework Colors – Incandescence You know how a stove burner is dark when its relatively cool, red when its hot, and white­hot when you turn it all the way up? This is incandescence of the heating element, which is light emitted by the element as it gets hot. Fireworks also rely on incandescence for special effects and colors. Certain chemicals are red, orange, yellow, and white when heated. In particular, metals are heated to produce colored sparks, glitter, and fountain effects. Titanium, iron, and aluminum flakes are common metals heated to incandescence in fireworks. Copyright © Savvas Learning Company LLC. All Rights Reserved. Savvas is not responsible for any modifications made by end users to the content posted in its original format. https://docs.google.com/document/d/1fPnBYBxG3HxUOutVq3BLdszgaZA4x3ZcVSYb420LrZ4/edit# 2/3 7/11/2019 CHEM21_AS_Authentic_Reading - Google Docs NAME DATE CLASS Firework Periodic Table Here’s a handy periodic table you can print that shows the principal elements used in fireworks. The table is color­coded, so you can see at a glance which colors are produced by heating certain elements. Credits Text: Firework Colors Chemistry by Anne Helmenstine/Sciencenotes.org. Reprinted with permission. Images: Anne Helmenstine/Sciencenotes.org and Todd Helmenstine/Sciencenotes.org Copyright © Savvas Learning Company LLC. All Rights Reserved. Savvas is not responsible for any modifications made by end users to the content posted in its original format. https://docs.google.com/document/d/1fPnBYBxG3HxUOutVq3BLdszgaZA4x3ZcVSYb420LrZ4/edit# 3/3
