Street light in many communities are sodium vapor lamps. These lamps visually have an orange-yellow tint. The visible emission spectrum for sodium shows that two prominent bands are detected within the visible color change. These light waves are both yellow and have wavelengths of about 590nm. This explains why the light produced from sodium vapor lamps would appear yellow and not white. in comparison, mercury vapor lamps produce a blue-colored light due to intense light emission from the mercury atoms that have a wavelength of about 434nm. Without any calculation, which element would you expect to produce higher energy photons in the visible part of spectrum?