Spectrum and the types of spectrum by Jayam chemistry learners

It briefly discusses about spectrum and the types of spectrum with detailed examples.

1. Spectrum and its
types
By
Jayam chemistry learners

2. A spectrum is a patterned arrangement of various light wavelengths
obtained by passing polychromatic radiation through the prism.
Spectrum
Every chemical element of the universe exhibits a unique atomic
spectrum. It helps to determine their deposits in a specific terrestrial or
astronomical object.
Hence, spectral studies play a vital role in the composition analysis of the
universal matter.

3. Types of spectrum
Emission
spectrum
Absorption
spectrum
Continuous
spectrum
Continuous
emission
spectrum
Discontinuous
emission
spectrum

4. It is a specimen of bright lines or bands obtained by analyzing the
emitted photons of an excited atom.
Emission spectrum
The expelled light radiations of excited atoms pass through the
spectrometer to produce their emission spectra.
The emission spectrum of an atom is of two kinds.
1. Continuous emission spectrum
2. Discontinuous emission spectrum

5. Continuous emission spectrum:
A continuous emission spectrum is a pattern of diffused glowing
bands merged into each other. Here, one color band consolidates
into the other without any separation.
There is no beginning or ending to the color bands of the
continuous emission spectrum. For example- The solar spectrum
of sunlight

6. Discontinuous emission spectrum:
It consists of a series of sharp lines separated by dark bands.
Here, the spectral lines are separate and unmerged. And each
spectral line corresponds to a particular wavelength or
frequency.
For example -The atomic spectra of chemical elements. Its
other name is the line spectrum which corresponds to the sharp
lines of the spectrum.

7. It is a pattern of dark lines or bands corresponding to the light
radiations absorbed by the substance. The transmitting light beam
acquired from the absorbing medium produces the absorption spectrum
when passed through the spectrometer.
Absorption spectrum
Absorbed light radiations of ground-state atoms generate their
absorption spectrum.

8. It consists of a definite range of all wavelengths of the electromagnetic
spectrum. The source of continuous spectra is hot celestial matter and
stars
Continuous spectrum
The range of wavelengths that occur in the continuous spectrum depends
upon the temperature of the emitted light source.

9. Sunlight that passes through the prism
shows a series of seven-colored diffused
bands called the solar spectrum. It is an
example of a continuous emission spectrum.
The seven colors of the solar spectrum are
Violet, Indigo, Blue, Green, Yellow, Orange,
and Red, called VIBGYOR.
Continuous Solar spectrum:

10. Sodium absorption
spectrum:
The most notable lines in the sodium
spectrum are the D-lines, which are
due to transitions of electrons between
the 3p and 3s orbitals.

11. We can observe sodium absorption through either of the following
methods:
(a) Pass white light through the vapors or a solution of sodium chloride
and analyze the transmitted light with a spectrograph. (b) Pass sunlight
through a prism after it has passed through a sodium chloride solution.
In both cases, the sodium absorption spectrum shows two dark lines at
5890 Å and 5896 Å, known as D1 and D2 lines.

12. Uses of spectral studies:
The study of the emission and absorption spectra of the substance
provides information on its structure. In particular, astronomers use this
spectroscopic data to determine the constituents of stars and interstellar
matter.
The study of light radiation's path in the intergalactic medium intimates
us about the stuff like gas or dust that fills the space between the stars
and galaxies. It tells the materials around the stars, galaxies, and other
interstellar objects.

13. What are spectrum and spectroscopy?
A spectrum is the range of different colors produced when light is
dispersed by a prism or diffraction grating, showing the different
wavelengths or frequencies of light. It can also refer to a range of other
types of electromagnetic radiation.
Spectroscopy is the scientific study of how light interacts with matter. It
involves analyzing the spectrum of light emitted, absorbed, or scattered
by materials to understand their properties, composition, and structure.

14. Emission spectrum Absorption spectrum
It is produced by analyzing the radiant
energy emitted by the excited substance
It is produced when white light is passed
through a substance and transmitted light
is analysed by a spectrograph
It consists of some bright lines
separated by dark spaces
It consists of dark lines in otherwise
continuous spectrum
Difference between emission and
absorption spectrum:

15. Thank you!
See you next time!