34.2: Introduction

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	\(h\)	\(c\)
\(E = \dfrac{hc}{\lambda}\)	\(6.626 \times 10^{-34}\) 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.

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