Search results
Results From The WOW.Com Content Network
Depiction of a hydrogen atom showing the diameter as about twice the Bohr model radius. (Image not to scale) A hydrogen atom is an atom of the chemical element hydrogen.The electrically neutral hydrogen atom contains a single positively charged proton in the nucleus, and a single negatively charged electron bound to the nucleus by the Coulomb force.
The Bohr radius ( ) is a physical constant, approximately equal to the most probable distance between the nucleus and the electron in a hydrogen atom in its ground state. It is named after Niels Bohr, due to its role in the Bohr model of an atom. Its value is 5.291 772 105 44 (82) × 10 −11 m. [1] [2]
Just as atomic units are given in terms of the atomic mass unit (approximately the proton mass), the physically appropriate unit of length here is the Bohr radius, which is the radius of a hydrogen atom. The Bohr radius is consequently known as the "atomic unit of length". It is often denoted by a 0 and is approximately 53 pm. Hence, the values ...
By 1900, various estimates of mercury atom diameter averaged around 275±20 pm [7] (modern estimates give 300±10 pm, see below). In 1920, shortly after it had become possible to determine the sizes of atoms using X-ray crystallography, it was suggested that all atoms of the same element have the same radii. [11]
A depiction of a hydrogen atom with size of central proton shown, and the atomic diameter shown as about twice the Bohr model radius (image not to scale) The ground state energy level of the electron in a hydrogen atom is −13.6 eV, [24] equivalent to an ultraviolet photon of roughly 91 nm wavelength. [25]
The Bohr model of the hydrogen atom (Z = 1) or a hydrogen-like ion (Z > 1), where the negatively charged electron confined to an atomic shell encircles a small, positively charged atomic nucleus and where an electron jumps between orbits, is accompanied by an emitted or absorbed amount of electromagnetic energy (hν). [1]
Get AOL Mail for FREE! Manage your email like never before with travel, photo & document views. Personalize your inbox with themes & tabs. You've Got Mail!
6 × 10-15 meters Average size of an atom's nucleus 10-14 meters — Uranium nucleus — 1.5 × 10-14 meters Picometer: 10-12 meters 10-12 meters Gamma ray wavelength 10-12 meters 10-12 meters Electron compton wavelength: 2 × 10-12 meters — Helium atom 3.1 × 10-11 meters 2.5 × 10-11 meters Hydrogen atom 2.5 × 10-11 meters 3.1 × 10-11 meters