i m sorry i was busy ..

Na is going to show line spectra (lines obtained at 589nm and 589.9nm) that is also called as atomic spectra.

 

HgO is compound so it w'll show band spectra.

band spectra is shown by compound and molecules.

 

W wire is used for making the filament of bulb used in spectrometers and it gv white light (act as black body). so that spectrum is continious one...

 

i m searching fr proper explanation of pt black spectra as soon as i'll get i'll expalin u...