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See a helium spectral tube with diffraction grating and the spectral lines of helium in nanometers. Learn about the energy levels and transitions of helium atoms and other elements.
Strong Lines of Helium ( He ) Intensity. Vacuum. Wavelength (Å) Spectrum. Reference.
A matching absorption spectrum occurs when light passes through a material and is absorbed by its atoms. The 12 lines of the visible helium spectrum correspond to wavelengths of 388.8, 447.1, 471.3, 492.1, 501.5, 504.7, 587.5, 667.8, 686.7, 706.5, 728.1 and 781.3 nanometres (nm).
Notes: The spectroscopic data below are for the isotope 4 He. He I Ground State 1s 2 1 S 0 Ionization energy 198310.669 cm-1 (24.587387 eV) Ref. M02 He II Ground State 1s 2 S 1 / 2 Ionization energy 438908.8789 cm-1 (54.417760 eV) Ref. MK00b-1 (54.417760 eV) Ref. MK00b
Table I. Calculated wavelengths of nine observed lines of helium spectrum compared with wavelengths of visible transitions found on the helium energy-level diagram.
1 Μαρ 1998 · When observing the spectrum of helium in an introductory physics laboratory, a complete and satisfactory laboratory experience that provides insight into the connection between the observed wavelengths and the structure of the atom, is more difficult to achieve than when observing hydrogen.
The emission spectrum (or line spectrum) of a chemical element is the unique pattern of light obtained when the element is subjected to heat or electricity. When hydrogen gas is placed into a tube and electric current passed through it, the color of emitted light is pink.
