Search results
Results From The WOW.Com Content Network
Diamond and graphite are two allotropes of carbon: pure forms of the same element that differ in crystalline structure.. Allotropy or allotropism (from Ancient Greek ἄλλος (allos) 'other' and τρόπος (tropos) 'manner, form') is the property of some chemical elements to exist in two or more different forms, in the same physical state, known as allotropes of the elements.
Carbon is capable of forming many allotropes (structurally different forms of the same element) due to its valency (tetravalent). Well-known forms of carbon include diamond and graphite. In recent decades, many more allotropes have been discovered and researched, including ball shapes such as buckminsterfullerene and sheets such as graphene.
Although white phosphorus forms the tetrahedron, the simplest possible Platonic hydrocarbon, no other polyhedral phosphorus clusters are known. [7] White phosphorus converts to the thermodynamically-stabler red allotrope, but that allotrope is not isolated polyhedra.
Phosphorus has several allotropes that exhibit strikingly diverse properties. [11] The two most common allotropes are white phosphorus and red phosphorus. [12] For both pure and applied uses, the most important allotrope is white phosphorus, often abbreviated WP. White phosphorus is a soft, waxy molecular solid composed of P 4 tetrahedra. This P
There are several known allotropes of oxygen. The most familiar is molecular oxygen (O 2), present at significant levels in Earth's atmosphere and also known as dioxygen or triplet oxygen. Another is the highly reactive ozone (O 3). Others are: Atomic oxygen (O 1), a free radical. Singlet oxygen (O * 2), one of two metastable states of ...
The element sulfur exists as many allotropes. In number of allotropes, sulfur is second only to carbon. [1] In addition to the allotropes, each allotrope often exists in polymorphs (different crystal structures of the same covalently bonded S n molecules) delineated by Greek prefixes (α, β, etc.). [2]
Iron allotropes, showing the differences in structure. The alpha iron (α-Fe) is a body-centered cubic (BCC) and the gamma iron (γ-Fe) is a face-centered cubic (FCC). At atmospheric pressure, three allotropic forms of iron exist, depending on temperature: alpha iron (α-Fe, ferrite), gamma iron (γ-Fe, austenite), and delta iron (δ-Fe).
Selenium forms several allotropes that interconvert with temperature changes, depending somewhat on the rate of temperature change. When prepared in chemical reactions, selenium is usually an amorphous, brick-red powder. When rapidly melted, it forms the black, vitreous form, usually sold commercially as beads. [14]