Search results
Results from the WOW.Com Content Network
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.
m is the molar conductivity at infinite dilution (or limiting molar conductivity), which can be determined by extrapolation of Λ m as a function of √ c, K is the Kohlrausch coefficient, which depends mainly on the stoichiometry of the specific salt in solution, α is the dissociation degree even for strong concentrated electrolytes,
Nonmetals show more variability in their properties than do metals. [1] Metalloids are included here since they behave predominately as chemically weak nonmetals.. Physically, they nearly all exist as diatomic or monatomic gases, or polyatomic solids having more substantial (open-packed) forms and relatively small atomic radii, unlike metals, which are nearly all solid and close-packed, and ...
As temperature rises, the conductivity of metals decreases while that of nonmetals increases. [243] However, plutonium, carbon, arsenic, and antimony appear to defy the norm. When plutonium (a metal) is heated within a temperature range of −175 to +125 °C its conductivity increases. [244]
In solid-state physics, the valence band and conduction band are the bands closest to the Fermi level, and thus determine the electrical conductivity of the solid. In nonmetals, the valence band is the highest range of electron energies in which electrons are normally present at absolute zero temperature, while the conduction band is the lowest range of vacant electronic states.
Electrical conductivity of water samples is used as an indicator of how salt-free, ion-free, or impurity-free the sample is; the purer the water, the lower the conductivity (the higher the resistivity). Conductivity measurements in water are often reported as specific conductance, relative to the conductivity of pure water at 25 °C.
As quoted from various sources in an online version of: David R. Lide (ed), CRC Handbook of Chemistry and Physics, 84th Edition.CRC Press. Boca Raton, Florida, 2003; Section 12, Properties of Solids; Thermal and Physical Properties of Pure Metals / Thermal Conductivity of Crystalline Dielectrics / Thermal Conductivity of Metals and Semiconductors as a Function of Temperature
Metals are insoluble in water or organic solvents, unless they undergo a reaction with them. Typically, this is an oxidation reaction that robs the metal atoms of their itinerant electrons, destroying the metallic bonding. However metals are often readily soluble in each other while retaining the metallic character of their bonding.