Everyone knows that you get yellow fire from burning wood, depending on what you add to a fire you can change the colour of its flame. The reason particular colours are given out is due to the energy level the ‘burning’ happens at. Remember the old period table? (or if you had modern enough science teacher; a periodic galaxy?) well its all down its arrangement.
The Sciencey Bit
(Skip this if you really don’t want to know why) The reason different compounds or elements produce different colours when burnt is the oxygen combines with them changing the arrangement of the atoms electrons.
Electrons form orbits or ‘shells’ with higher levels of potential energy for each one in each each orbit, filling up the bottom orbits first. When an electron is exchanged from one shell to another light (photons) must be emitted with an energy matching the change in ‘height’ (potential energy) to maintain balance. The energy of a photon is determined by the Planck constant multiplied by its frequency (E = h×?) which means that different energies result in different frequencies some of which can be seen as a colour.
The Example Bit
The most readily known examples of coloured fire are interstellar stars, although in all honesty they’re not really balls of fire but energy releasing spheres of luminous plasma. Anyway, they come in a variety of different colours depending on there temperature which is based on there dominant fuel, in the The Sun’s case it is 75% Hydrogen and 24% Helium giving it a yellow colour from our atmosphere. As the Sun ages the Hydrogen will become Helium through fusion and it will appear red, just like the the Sun Krypton orbits in Superman and it is called what is known as a Red Dwarf. As the Helium ‘burns’ together into even denser materials it will eventually change to White Dwarf.
Another example that is slightly more down to Earth is the use of different compounds for stunning sky bound effects called fireworks. To produce the most brilliant colours other elements are used to enhance the colour produced from burning, usually Chlorine, which is toxic in large amounts.
The Safety Bit
WARNING: I wouldn’t suggest acquiring any of these elements and trying it out for yourself, especially since some of these substances alone are radioactive, toxic or both! This is intended as a reverse lookup; you see the colour then work out what made it. I’ve not listed every substance just the ones I could find any information on.
The Referencey Bit
|Alkaline Earth||Violent Reaction in Moisture, White Fume|
|Transition||Gold||Easily Magnetic, Symbol from the Word ‘Ferrum’|
|Alkali||Silvery White||Easily Cut with Knife, Reactive with Water, White Fume|
|Transition||Silvery Metallic||Yellowish green||Poisonous, esp. if inhaled|
|Transition||Grey Metallic||Yellowish green||May have facilitated multicellular lifeforms|
|Alkali Earth||Mades rare Gem Benitoite|
|Metalloids||(Deep) Brown||Bright green||Used in Scientific Glassware|
|Poor||Silvery White||Pure green||Highly Toxic|
|Metalloids||Lustrous Silver||Pale Green|
|Non||Dull Red with White Sheen||Pale bluish green||Reactive when Cut, therefore used in Matches|
|Poor||Blue||Slightly Radioactive, Very Low Toxicity, Yellow Fume|
|Poor||Light Grey||Blue||Used in Liquid Crystal Displays, Toxic|
|Post-transition||Blue||High Density, Toxic, Stops Xrays Easily|
|Non||Dark Grey with metallic sheen||Azure blue||Key Ingredient in Head’n’Shoulders, MacGuffin in Evolution|
|Alkali Metal||Silvery White||Highly Reactive with Water|
|Alkali||Grey White||Highly Reactive with Water OR air|
|Poor||White||Common Use, Very High Strength:Weight Ratio|
|Alkaline Earth||White Fume|
|Transition||White||Food Colourant E171 (Titanium Dioxide)|