Science Art: Bunsen burner flame types, by Arthur Jan Fijałkowski (WarX).

Scientific illustration of different kinds of flames produced by a Bunsen burner
Scientific illustration of different kinds of flames produced by a Bunsen burner

The flame from a Bunsen burner (a standard piece of chemistry equipment; you might have used one in high school) can change color and height depending on how much air flows into the jet of fuel.

These flames show:

  1. air valve closed
  2. air valve nearly fully closed
  3. air valve semi-opened
  4. air valve maximally opened

I found the image in Wikimedia Commons.