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Namangan Institute of Engineering and Technology
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Bog'liq ТўпламNamangan Institute of Engineering and Technology
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10.25.2023
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matching the colors of the dispersion spectrum, is called the dispersion angle: the width of the
spectrum depends on this angle and is calculated using the formula;
(n
1) (1)
The external appearance of the spectra can vary greatly depending on the characteristics of
the light source in a dark environment. There are three main types of spectra: continuous spectra,
line spectra, and band spectra. Continuous spectra encompass all colors (wavelengths), transitioning
smoothly from one color to the next (Figure 4a).
Figure 4a
The line spectrum consists of distinct, narrow, dark intervals separated by wide black regions
(Figure 4b).
Figure 4b
Each line corresponds to a specific wavelength of light. The band spectrum is a distinct group
formed by a large number of closely spaced lines. The lines within each group are so closely packed
that when viewed through a tool with limited resolution, they appear as a single band (Figure 4-d).
Figure 4d
In this way, each path corresponds to a specific interval of light wavelength.
The interaction between line spectra is the result of individual atoms that have absorbed light.
This is due to the transition of the involved electrons to lower energy levels (orbitals).
Band spectra, on the other hand, result from interactions among individual molecules.
In atoms, the emission of light is due to the vibrational motions of atoms in molecules, similar
to the transitions of electrons in atoms.
The combination of molecules and atomic ions that interact with each other produces the
spectra of continuous spectra. In this case, chaotic motion (vibration and rotation) plays a major
role, which occurs due to the higher states of the particles.
Therefore, the emission spectra of condensed and solid bodies and condensed gases differ
from the ones mentioned earlier. Excited gases (atoms and molecules, for example, excited by
heating or electrical discharge) exhibit line and band spectra. Single-atom gases, on the other hand
(inert gases, metal vapors, dissociated multiple-atom gases), exhibit line spectra.
For each chemical element (in a gaseous or condensed state), its characteristic emission
spectrum exists, characterized by the number of spectral lines, their colors, and their arrangement.
The spectral method (spectral analysis) is based on identifying the chemical composition of
substances.
If the source of the emission spectrum is initially a condensed gas (or solid), then in the
spectrum, the emission lines (or bands) of that gas will appear. Such a spectrum is called an
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