Flame Luminosity

The flames studied in this experiment emit light in the visible spectral region. One source of this light is emissions from molecules that are formed in an excited electronic state and then return to a lower state (ground state) with the emission of a photon (light). The color of the light is related to the energy change by the relationship: DE = hn = hc/l. Another source is the "black body" radiation from the soot particles that form when hydrocarbons burn. The amount of soot formed is dependent upon the flame temperature, as is the wavelength distribution of the light. This type of spectral information may be used to determine the species type and concentration, and the local temperature in a flame. Laser spectroscopy is frequently used in this context.