Question

describe spectrum from the Na source

Answer 1

When the vapour of the element is kept in a discharge tube and subjected to high potential then line spectrum is obtained.

For example :

Sodium gives two bright lines of wavelengths 5890A⁰ and 5896A⁰ in the yellow region.

They are separated by dark space.

Example:
 sodium vapour lamp is a gas discharge lamp that uses sodium in an excited state to produce light at an charcteristics wavelength near 589nm.