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Summary
DescriptionCool colored candles, with metal salts from our rocket propellants (13049862325).jpg
The birthday month Marches on!
These special candles on my cake are really cool. The flame colors are just like the propellant colors we have in our solid rocket motors. Metal ions combine with electrons in the flame, and the metal atoms are raised to excited states because of the high flame temperature. Upon returning to the ground state, they give off a pure wavelength of light (from their line spectrum) characteristic of that metal.
The ions come from metal chlorides: Barium Chloride (BaCl) for green, Copper Chloride (CuCl) for blue, or Strontium Chloride (SrCl) for red. Here is a primer on rocket propellants with photos of my rockets flying with the various colors.
Date
Source
Cool colored candles, with metal salts from our rocket propellants
Author
Steve Jurvetson
Camera location
37° 30′ 07.21″ N, 122° 28′ 28.18″ W
View this and other nearby images on: OpenStreetMap
37.502003; -122.474494
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This image was originally posted to Flickr by jurvetson at https://www.flickr.com/photos/44124348109@N01/13049862325. It was reviewed on 10 May 2015 by FlickreviewR and was confirmed to be licensed under the terms of the cc-by-2.0.
10 May 2015
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