<P> The emission spectrum of a chemical element or chemical compound is the spectrum of frequencies of electromagnetic radiation emitted due to an atom or molecule making a transition from a high energy state to a lower energy state . The photon energy of the emitted photon is equal to the energy difference between the two states . There are many possible electron transitions for each atom , and each transition has a specific energy difference . This collection of different transitions , leading to different radiated wavelengths , make up an emission spectrum . Each element 's emission spectrum is unique . Therefore , spectroscopy can be used to identify the elements in matter of unknown composition . Similarly , the emission spectra of molecules can be used in chemical analysis of substances . </P>
<P> The emission spectrum of a chemical element or chemical compound is the spectrum of frequencies of electromagnetic radiation emitted due to an atom or molecule making a transition from a high energy state to a lower energy state . The photon energy of the emitted photon is equal to the energy difference between the two states . There are many possible electron transitions for each atom , and each transition has a specific energy difference . This collection of different transitions , leading to different radiated wavelengths , make up an emission spectrum . Each element 's emission spectrum is unique . Therefore , spectroscopy can be used to identify the elements in matter of unknown composition . Similarly , the emission spectra of molecules can be used in chemical analysis of substances . </P>
when does emission of light from an atom occur
when does emission of light from an atom occur
an atom or molecule making a transition from a high energy state to a lower energy state
an atom or molecule making a transition from a high energy state to a lower energy state