Types of spectra - Emission spectra, Line spectrum, Band Spectrum, Absorption Spectra PDF

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Types of spectra - Emission spectra, Line spectrum, Band Spectrum, Absorption Spectra...

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Types of spectra - Emission spectra, Line spectrum, Band Spectrum, Absorption Spectra        

(i) Emission spectra. Continuous spectrum. Line spectrum. Band Spectrum. (ii) Absorption Spectra. 1 Fraunhofer lines. Fluorescence. Phosphorescence. When electromagnetic radiation is passed through a prism or grating it is split up and forms a collection of lines representing different wavelengths. This is called spectrum. The spectra can be divided into two types viz., emission and absorption spectra. The differences between them are given below. Emission Spectrum

Absorption Spectrum

1) The emission spectrum is obtained due to emission of radiation from the substances.

The absorption spectrum is obtained when the substance absorbs the radiation.

2) White lines are formed on the black background.

Black lines are formed on the white background.

3) Formed when atoms or molecules are deexcited from higher energy level to lower energy level.

Formed when atoms or molecules are excited from lower energy level to higher energy levels.

CONTINUOUS SPECTRUM. A spectrum (as of light emitted by a white-hot lamp filament) having no apparent breaks or gaps throughout its wavelength range....