Final answer:
Calcium and barium produce different flame colors due to their unique electron configurations that result in distinct emission spectra.
Step-by-step explanation:
The different flame colors produced by calcium and barium are attributable to their distinct electron configurations, which influence the wavelengths of light they emit upon excitement and subsequent relaxation of their electrons. Both calcium and barium are alkaline earth metals and impart specific colors to a flame which are indicative of the emission spectra of these elements. The colors are a result of electrons transitioning between energy levels.
When calcium or barium compounds are introduced into a flame, the energy from the flame excites electrons in the metal ions. These excited electrons then return to their ground state by emitting photons of light. The energy difference between the excited state and the ground state determines the wavelength of light emitted, with each element having a unique emission spectrum. The electron configuration of calcium allows it to produce red shades, while barium produces a green color due to its different electron configuration.
The complexity observed in the spectrum of calcium when compared to hydrogen is because calcium has more electrons and available energy levels, resulting in a larger number of possible transitions, yielding a more complicated emission spectrum. These unique emissions are used in the analysis of substances through flame tests where unknown substances can be identified by their characteristic flame color.