Key difference: A ‘line emission spectrum’ is obtained when the emission occurs from an atom, where the lines are usually unique and distinct in nature, while a ‘band emission spectrum’ is in the form of continuous bands that are obtained from molecules.

Emission is the process by which a higher energy quantum mechanical state of a particle gets converted to a lower form through the emission of a photon, resulting in the production of light. In emission, the spectrums of bright lines, bands, or continuous radiations are the characteristics which are determined by specific emitting substances and subjected to a specific kind of excitation. These spectrums are obtained from gases like hydrogen, helium, lithium, mercury, etc.

In simple terms, a line emission spectrum consists a variety of frequencies of electromagnetic radiations, generally emitted by elements, atoms or compound molecules at their lower energy states. Each emission spectrum in a line emission is unique and distinct in nature.

A band emission spectrum is generally obtained from various line spectra. These are closely spaced together in a continuous state. Unlike line spectrum, the band spectra are obtained from various line spectra, while they differ in characteristics and properties. In physics, band emission is described as a fraction of the total emission from a blackbody, which comes in different intervals among certain wavelengths (which are called as bands).

Spectral emission lines are extraordinarily useful in astronomy, physics, quantum mechanics, chemistry, etc. These emissions deal distinctly with the 'spectroscopy emission' concept. The mentioned emission is a spectroscopic technique that examines the wavelengths of photons emitted by atoms/molecules during their transition from an excited state to a lower energy state.

Comparison between Line Emission Spectrum and Band Emission Spectrum:

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