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CHEM 121 Studioby Learn4Less · UBC CHEM 121

CHEM 121 glossary

Visible light

The narrow part of the electromagnetic spectrum the human eye detects, about 400 to 750 nm. Violet is the short-wavelength, high-energy end and red the long-wavelength, low-energy end.

Line spectrumBright emission lines at 700 nm, 530 nm, 470 nm, 400 nm.← UVIR →< 380 nm> 750 nm400450500550600650700750wavelength (nm)700 nm530 nm470 nm400 nm

Red (700 nm), green (530 nm), blue (470 nm) and violet (400 nm).

Example

A 700 nm red photon carries 171 kJ/mol and a 400 nm violet photon 299 kJ/mol, so visible photons span roughly 170 to 300 kJ/mol.

See alsoElectromagnetic spectrumWavelengthComplementary colour