Question

The emission spectra of Sample $A$

• A. Must have $3$ lines
• B. Must have $2$ lines
• C. Must have $4$ lines
• D. It is not formed

Answer 1

The correct option is D It is not formed

When electron get excited to higher level, then it comes down the lower energy level emitting a photon of certain wavelength, and so an emission spectrum forms.

But as the atoms of sample A remain in the ground state although after passing a photon beam, this means the electron remains in the ground state all the time (i.e never get excited to higher energy lavel) and hence the emission spectrum is not formed.