Emission & Absorption Spectrum Game
Fire photons at a gas, compare bright emission lines with dark absorption lines, then identify mystery spectra.
Fire photons at a gas, compare bright emission lines with dark absorption lines, then identify mystery spectra.
Atoms have discrete energy levels. A photon is absorbed only if its energy exactly equals a gap ΔE between two levels: ΔE = hc/λ.
Emission: an excited electron drops down and releases a photon of that same ΔE — bright coloured lines on a dark background.
Absorption: a cool gas sits in front of a hot continuous source. Photons with matching λ are removed — dark lines on a rainbow.
That is why every dark Fraunhofer line of an element sits at the identical wavelength as one of its bright emission lines.