each element (as seen in the picture) has it's own emission spectrum. you may call it a 'fingerprint that is unique to each
element
explain why hydrogen and oxygen have a different number of line spectra.
the transition of electrons between energy levels causes energy of various
wavelengths to be given off. they are seen as line spectra hydrogen is
much lighter than oxygen which results in fewer line spectra
as electrons transition between energy levels, they give off energy of
various wavelengths which can be observed as line spectra. oxygen has
more electrons than hydrogen which leads to more possible line spectra.
with more electrons and energy levels, oxygen is capable of producing
more combinations of electromagnetic radiation which can be viewed as
line spectra. hydrogen has only one energy level so it will have the least
line spectra
oxygen has more energy levels than hydrogen which allows it to have
more possible wavelengths which can be observed as line spectra
oxygen's electrons have two possible energy levels to move between
rather than the one level that hydrogen has.