on page no.41 fig. 2.10 of ncert chemistry book in emission spectrum first there is blue colour then rest of the portion is of black colour....so is that black portion part of the visible spectrum?

Asked by Aditi Srivastava | 12th Aug, 2014, 10:03: PM

Expert Answer:

Dear aditi9714srivas@gmail.com

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The diagram about which you are talking is not visible spectrum, it is a line emission spectra. The black portion is not the part of line spectrum. Please see that diagram again, you will find lines of various colours like green, yellow, red etc. those are part of line spectrum. The emission spectra of atoms in the gas phase do not show a continuous spread of wavelength, they emit light only at specific wavelengths with dark spaces between them. The emitted radiation is identified by the appearance of bright lines (green, yellow, red etc.) in the spectra. When there is no detection of wavelength dark spaces are observed.

For your reference I have given below visible spectrum:


Topperlearning Team.

Answered by Arvind Diwale | 14th Aug, 2014, 04:33: PM

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