Emission Spectra and the Electromagnetic Spectrum

Light is a form of electromagnetic radiation, and understanding its behavior is the key to unlocking the arrangement of electrons in atoms. Electromagnetic radiation can be described by its wavelength $\lambda$, the distance between successive wave crests, and its frequency $\nu$, the number of waves passing a point per second. These are linked by the speed of light $c$ through $c = \lambda\nu$, so that wavelength and frequency are inversely related: as wavelength increases, frequency decreases. The electromagnetic spectrum orders radiation by wavelength, running from long-wavelength, low-frequency radio waves through microwaves, infrared, the narrow band of visible light, then ultraviolet, X-rays, and finally short-wavelength, high-frequency, high-energy gamma rays. Within the visible reg