Search results
Results from the WOW.Com Content Network
a. ductile and malleable elements are metals; b. hard and brittle elements include boron, silicon and germanium, which are semiconductors and therefore not metals; and c. soft and crumbly elements include carbon, phosphorus, sulfur, arsenic, antimony, [ag] tellurium and iodine, which have acidic oxides indicative of nonmetallic character. [ah]
Stellar interior specialists use 'metals' to designate any element other than hydrogen and helium, and in consequence ‘metal abundance’ implies all elements other than the first two. For spectroscopists this is very misleading, because they use the word in the chemical sense.
A material property is an intensive property of a material, i.e., a physical property or chemical property that does not depend on the amount of the material. These quantitative properties may be used as a metric by which the benefits of one material versus another can be compared, thereby aiding in materials selection.
The chemical elements can be broadly divided into metals, metalloids, and nonmetals according to their shared physical and chemical properties.All elemental metals have a shiny appearance (at least when freshly polished); are good conductors of heat and electricity; form alloys with other metallic elements; and have at least one basic oxide.
Main page; Contents; Current events; Random article; About Wikipedia; Contact us; Pages for logged out editors learn more
It has the lowest boiling point of all of the elements. Liquid helium exhibits super-fluidity, superconductivity, and near-zero viscosity; its thermal conductivity is greater than that of any other known substance (more than 1,000 times that of copper). Helium can only be solidified at −272.20 °C under a pressure of 2.5 MPa.
The minimum distance between chains is 343.6 pm. Gray selenium is formed by mild heating of other allotropes, by slow cooling of molten selenium, or by condensing selenium vapor just below the melting point. Whereas other selenium forms are insulators, gray selenium is a semiconductor showing appreciable photoconductivity.
The other six isotopes forming 82.7% of natural tin have capture cross sections of 0.3 barns or less, making them effectively transparent to neutrons. [30] Tin has 31 unstable isotopes, ranging in mass number from 99 to 139. The unstable tin isotopes have half-lives of less than a year except for tin-126, which has a half-life of