Flame test
The flame test is mainly caused by metallic elements contained in the material.
And, the same reaction occurs when it exists as a pure substance as well as when it is chemically bonded to another substance.
![](/lee/contents/flame_test_1.png)
The principle of the flame test
The flame test occurs when electrons that are excited by receiving thermal energy return to their original orbit and emit light with a wavelength corresponding to the energy difference.
The energy orbits of electrons are quantized, and each orbit has different spacing, so each element has its unique color of the flame test.
![](/lee/contents/quantom_leap_1.gif)
![](/lee/contents/quantom_leap_2.gif)
The different colors of fireworks are the use of the pyrotechnic reaction of metallic elements.
![](/lee/contents/firework.jpg)
Continuous spectrum
Incandescent bulbs emit light in all visible wavelengths by thermoelectrons. The spectrum’s continuous view is not only because a specific value of energy is emitted but because energy is evenly emitted over the entire visible range.
The continuous spectrum is well observed in a dense state because the atom’s electron orbits interfere with each other and cannot emit their own light. (E.g., solid or liquid, dense gas)
![](/lee/contents/spectrum_bulb_na.gif)
Line spectrum
When looking at the spectrum of light emitted from a fluorescent lamp, sodium lamp, neon sign, or flame test, only distinct wavelengths of light appear. The observed spectrum is called a line spectrum because it looks like a bar code.
Line spectra are well observed in sparse conditions because the atoms must emit their own light without interfering with each other. (E.g., gas or plasma state)