What would have been another way of exciting the electrons without using a bunsen burner?

The another way of exciting the electrons without using a bunsen burner is by using microwave owen as it heats by exciting electrons directly without using a flame.There are several opportunities to excite electrons within an atom or a molecule.The energies to excite a single electron in an atom start at roughly 10-19J, which is approximately the energy of red light.

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