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How to Make a Rainbow Spectrum Using Chemicals

All those colors you see light up the sky during a fireworks show are actually small pieces of metal that are burning up. As metal burns, it gives off a unique color. Since metals aren't flammable, they require an oxidant, but all chemicals can burn and not all chemicals burn with an orange flame. It's possible to create the entire rainbow spectrum (red, orange, yellow, green, blue, indigo and violet) with chemicals like metal salts.

Things You'll Need

Seven alcohol flame lamps
Ethanol
Strontium nitrate
Sodium chloride
Barium nitrate
Cupric chloride
Potassium chloride

Instructions

- 1
  Add one gram of strontium nitrate to 100 ml of ethanol in the first alcohol flame lamp. This flame will burn red.
- 2
  Add three quarters of one gram of strontium nitrate and one quarter of one gram of sodium chloride to 100 ml of ethanol in the second flame lamp. Sodium is a strong pyrotechnic agent so add less of it than strontium nitrate to the fuel of this lamp. If the flame is too yellow, add more strontium nitrate. This flame will be orange.
- 3
  Add one gram of sodium chloride to 100 ml of ethanol in the third alcohol flame lamp. This flame will be yellow. Alternatively, it's possible to forgo adding any salt at all since ethanol burns with a yellow flame naturally.
- 4
  Add one gram of barium nitrate to 100 ml of ethanol in the fourth alcohol flame lamp. This flame will be green.
- 5
  Add one gram of cupric chloride to 100 ml of ethanol in the fifth alcohol flame lamp. This flame will burn blue.
- 6
  Add one half gram of cupric chloride and one half gram of potassium chloride with 100 ml of ethanol in the sixth alcohol flame lamp to achieve an indigo flame.
- 7
  Add one gram of potassium chloride to 100 ml of ethanol in the seventh and final alcohol flame lamp.
- 8
  Light all the lamps at once and view your chemically-produced rainbow.

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