The generation of spectral wavelengths

Any substance is composed of elements, and the elements are composed of atoms, atoms are composed of nuclei and electrons, each electron is in a certain energy level, with a certain energy, in the normal state, the atom is in a stable state, its lowest energy, this state is called the ground state. When the material is affected by external energy (electrical energy and heat), the exuclear electrons transition to a high energy level, in the high energy state (excited state) electrons are unstable, excited state atoms can exist for about 10-8 seconds, it from the high energy state transition to the ground state, or lower energy state, the excess energy is released in the form of light.

Because the ground state of each element is not the same, the excited state is not the same, so the emitted photons are inconsistent, that is, the wavelength is not the same.

According to the wavelength λ can determine which element, this is the qualitative analysis of the spectrum. On the other hand, the intensity of the spectral line is determined by the number of photons emitting the spectral line, the number of photons is large, the intensity is weak, and the number of photons is determined by the number of atoms in the ground state, and the number of ground state atoms depends on the content of an element, so that the content of an element can be obtained according to the intensity of the spectral line.