Hlo every one ☺☺here is my question explain me about types of spectrum.
Answers
Types of Atomic Spectrum
(1) Emission spectrum:
Spectrum produced by the emitted radiation is known as emission spectrum. This spectrum corresponds to the radiation emitted (energy evolved) when an excited electron returns back to the ground state.
(i) Continuous spectrum:
When sunlight is passed through a prism, it gets dispersed into continuous bands of different colours. If the light of an incandescent object resolved through prism or spectroscope, it also gives continuous spectrum of colors.
(ii) Line spectrum:
If the radiation’s obtained by the excitation of a substance are analyzed with help of a spectroscope a series of thin bright lines of specific colors are obtained. There is dark space in between two consecutive lines. This type of spectrum is called line spectrum or atomic spectrum..
(2) Absorption spectrum:
Spectrum produced by the absorbed radiations is called absorption spectrum.
(3) Hydrogen spectrum:
Hydrogen spectrum is an example of line emission spectrum or atomic emission spectrum.
(a) When an electric discharge is passed through hydrogen gas at low pressure, a bluish light is emitted.
(b) This light shows discontinuous line spectrum of several isolated sharp lines through prism.
(c) All these lines of H-spectrum have Lyman, Balmer, Paschen, Barckett, Pfund and Humphrey series. These spectral series were named by the name of scientist discovered them.
(d) To evaluate wavelength of various H-lines Ritz introduced the following expression,
V- = 1/λ = V/C = [1/n12 - 1n22 ]
Where R is universal constant known as Rydberg’s constant its value is 109, 678 cm-1.
When Newton did his famous experiment with a prism and sunlight, he noted that the Sun produced a “rainbow” of colours. This is a continuous spectrum. (However, as I will discuss in a future blog, if he had been able to produce a more detailed spectrum he would have noticed some subtleties on this continuous spectrum). So, light from the Sun, and any star, produces a continuous spectrum.
We also get a continuum spectrum from a hot solid, so for example the light produced by incandescent light bulbs is a continuum spectrum. These kinds of bulbs give off light by a very thin coil of metal, the filament, (usually tungsten) getting extremely hot from having an electric current passed through it. When the filament gets to thousands of degrees, it gives off light.
An emission line spectrum
If, instead of looking at the spectrum of the Sun we were to look at the spectrum of an object like Messier 42 (the Orion nebula), we would notice a very different kind of spectrum. Rather than being a continuous spectrum, we would see a series of bright lines with a dark background. We would also see an emission line spectrum if we were to look at the spectrum from one of the fluorescent light sources which are now replacing the incandescent lights in houses.
An absorption line spectrum
An absorption line spectrum is in some ways the converse of an emission line spectrum. Rather than seeing a series of bright lines on a dark background, one sees dark lines on a continuous spectrum.
I hope this helps...