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34.2: Introduction

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    As electrons jump from one energy state to another within an atom, the atom absorbs and emits a quantum of energy specific to the jump.  The quantum of energy is called a photon.  Since light exhibits both particle and wave properties at the same time, each photon is associated with a particular wavelength and energy.  

    Table \(\PageIndex{1}\)

    Energy per Photon



    \(E = \dfrac{hc}{\lambda}\)

    \(6.626 \times 10^{-34}\) J s

    \(3 \times 10^8\) m/s

    Every atom in the periodic table has unique energy levels, and thus, emits a unique pattern of photons.  The pattern of emission lines produced by photons when a gas is excited, is called an atomic spectrum.  

    Figure \(\PageIndex{1}\): Example Atomic Spectrum. Emission Spectrum is under public domain

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    34.2: Introduction is shared under a CC BY license and was authored, remixed, and/or curated by LibreTexts.

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