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Wavelength Amplitude Frequency Speed. 1900 – Max Planck. 1905 – Albert Einstein. The Photoelectric Effect. When light is shone onto a metal surface, electrons are ejected from the surface. The Photoelectric Effect. The Photoelectric Effect. “The particle-wave duality of light”.
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Wavelength Amplitude Frequency Speed
The Photoelectric Effect When light is shone onto a metal surface, electrons are ejected from the surface.
“The particle-wave duality of light” Light has particle-like properties as well as wave-like properties.
1913 – Niels Bohr Hydrogen Line Emission Spectrum
1913 – Niels Bohr • The electron in a hydrogen atom is usually in the n = 1 energy level. This is called the ground state for that atom. • When energy is supplied, the electron can move into a higher energy level. The atom is then said to be in an excited state. • When the e- returns to its ground state, energy is released.
1924 – Louis de Broglie Any particle of mass m moving with a velocity v will have a de Broglie wavelength given by the following equation: = h mv A particle of matter has a wavelength!
Order of Orbital Filling? 1s 2s 2p 3s 3p 4s 3d 4p 5s 4d 5p
Order of Orbital Filling? 1s 2s 2p 3s 3p 4s 3d 4p 5s 4d 5p WHY? • Sublevel Energy Splitting • Coulomb’s Law • Shielding and Penetration • Spatial distribution of electrons in sublevels
Shielding image from chemwiki.ucdavis.edu
4s 3d Distance from nucleus