This is the question I found in the book with no answer.
Explain why the wavelengths of the emission lines for gas atoms of a particular elements have the same wavelengths as the dark absorption lines for the same atoms.
I thought it was because the atoms have specific energy levels, which meant that they only release photons of specific energies.
This means that the same atoms only absorb photons with the same frequency, hence the lines in both spectra are the same.
Can someone refine my answer or guide me if I am wrong?
Thanks.