Matches in DBpedia 2014 for { <http://dbpedia.org/resource/Atomic_radius> ?p ?o. }
Showing items 1 to 50 of
50
with 100 items per page.
- Atomic_radius abstract "The atomic radius of a chemical element is a measure of the size of its atoms, usually the mean or typical distance from the nucleus to the boundary of the surrounding cloud of electrons. Since the boundary is not a well-defined physical entity, there are various non-equivalent definitions of atomic radius. Three widely used definitions of atomic radius are Van der Waals radius, ionic radius, and covalent radius.Depending on the definition, the term may apply only to isolated atoms, or also to atoms in condensed matter, covalently bound in molecules, or in ionized and excited states; and its value may be obtained through experimental measurements, or computed from theoretical models. Under some definitions, the value of the radius may depend on the atom's state and context.Electrons do not have definite orbits, or sharply defined ranges. Rather, their positions must be described as probability distributions that taper off gradually as one moves away from the nucleus, without a sharp cutoff. Moreover, in condensed matter and molecules, the electron clouds of the atoms usually overlap to some extent, and some of the electrons may roam over a large region encompassing two or more atoms.Under most definitions the radii of isolated neutral atoms range between 30 and 300 pm (trillionths of a meter), or between 0.3 and 3 angstroms. Therefore, the radius of an atom is more than 10,000 times the radius of its nucleus (1–10 fm), and less than 1/1000 of the wavelength of visible light (400–700 nm).For many purposes, atoms can be modeled as spheres. This is only a crude approximation, but it can provide quantitative explanations and predictions for many phenomena, such as the density of liquids and solids, the diffusion of fluids through molecular sieves, the arrangement of atoms and ions in crystals, and the size and shape of molecules.[citation needed]Atomic radii vary in a predictable and explicable manner across the periodic table. For instance, the radii generally decrease along each period (row) of the table, from the alkali metals to the noble gases; and increase down each group (column). The radius increases sharply between the noble gas at the end of each period and the alkali metal at the beginning of the next period. These trends of the atomic radii (and of various other chemical and physical properties of the elements) can be explained by the electron shell theory of the atom; they provided important evidence for the development and confirmation of quantum theory. The atomic radii decreases across the Periodic Table because as the atomic number increases, the number of protons increases across the period, but the extra electrons are only added to the same quantum shell. Therefore, the effective nuclear charge towards the outermost electrons increases, drawing the outermost electrons closer. As a result, the electron cloud contracts and the atomic radii decreases.".
- Atomic_radius thumbnail Helium_atom_QM.svg?width=300.
- Atomic_radius wikiPageID "48900".
- Atomic_radius wikiPageRevisionID "580147994".
- Atomic_radius hasPhotoCollection Atomic_radius.
- Atomic_radius subject Category:Atoms.
- Atomic_radius subject Category:Properties_of_chemical_elements.
- Atomic_radius type Abstraction100002137.
- Atomic_radius type Atom114619225.
- Atomic_radius type Atoms.
- Atomic_radius type Matter100020827.
- Atomic_radius type Part113809207.
- Atomic_radius type PhysicalEntity100001930.
- Atomic_radius type Possession100032613.
- Atomic_radius type PropertiesOfChemicalElements.
- Atomic_radius type Property113244109.
- Atomic_radius type Relation100031921.
- Atomic_radius type Substance100019613.
- Atomic_radius comment "The atomic radius of a chemical element is a measure of the size of its atoms, usually the mean or typical distance from the nucleus to the boundary of the surrounding cloud of electrons. Since the boundary is not a well-defined physical entity, there are various non-equivalent definitions of atomic radius.".
- Atomic_radius label "Atomic radius".
- Atomic_radius label "Atomradius".
- Atomic_radius label "Atoomstraal".
- Atomic_radius label "Promień atomowy".
- Atomic_radius label "Radio atómico".
- Atomic_radius label "Raggio atomico".
- Atomic_radius label "Raio atómico".
- Atomic_radius label "Rayon atomique".
- Atomic_radius label "Радиус атома".
- Atomic_radius label "نصف قطر ذري".
- Atomic_radius label "原子半径".
- Atomic_radius label "原子半径".
- Atomic_radius sameAs Atomový_poloměr.
- Atomic_radius sameAs Atomradius.
- Atomic_radius sameAs Radio_atómico.
- Atomic_radius sameAs Erradio_atomiko.
- Atomic_radius sameAs Rayon_atomique.
- Atomic_radius sameAs Jari-jari_atom.
- Atomic_radius sameAs Raggio_atomico.
- Atomic_radius sameAs 原子半径.
- Atomic_radius sameAs 원자_반지름.
- Atomic_radius sameAs Atoomstraal.
- Atomic_radius sameAs Promień_atomowy.
- Atomic_radius sameAs Raio_atómico.
- Atomic_radius sameAs m.0d1jz.
- Atomic_radius sameAs Q483788.
- Atomic_radius sameAs Q483788.
- Atomic_radius sameAs Atomic_radius.
- Atomic_radius wasDerivedFrom Atomic_radius?oldid=580147994.
- Atomic_radius depiction Helium_atom_QM.svg.
- Atomic_radius isPrimaryTopicOf Atomic_radius.