Oxygen, elemental ozone

A number of chemical elements, mainly oxygen and carbon but also others, such as tin, phosphorus, and sulfur, occur naturally in more than one form. The various forms differ from one another in their physical properties and also, less frequently, in some of their chemical properties. The characteristic of some elements to exist in two or more modifications is known as allotropy, and the different modifications of each element are known as its allotropes. The phenomenon of allotropy is generally attributed to dissimilarities in the way the component atoms bond to each other in each allotrope either variation in the number of atoms bonded to form a molecule, as in the allotropes oxygen and ozone, or to differences in the crystal structure of solids such as graphite and diamond, the allotropes of carbon. 

So far as the terrestrial atmosphere is concerned, the dissociation of molecular oxygen by ultraviolet radiation leads to the formation of ozone (03) in dry air, which consists essentially of 78% nitrogen, 21% oxygen, and 1% argon. It follows that the characteristic element in the chemistry of the terrestrial atmosphere is oxygen in its three forms 02, O, and 03, since nitrogen is not dissociated by the radiations absorbed by oxygen and ozone. 

The BCNO elements also play an important part in how the Earth itself looks today. For instance, the oxygen gas ozone is part of a layer in the atmosphere that protects the planet from the Sun s damaging radiation. Plants constantly change carbon dioxide gas into the oxygen and food that keeps animals alive. Gasoline, oil,... 

The other form of elemental oxygen is ozone (O3), a molecule that can be represented by the resonance structures... 

The existence of an elementary substance in two forms is called allotropy (Greek alldtropia, variety, from alios, other, and tropos, direction). Ordinary oxygen and ozone are the allotropes of oxygen. Allotropy is shown by many elements it is due either to the existence of two or more kinds of molecules (containing different numbers of atoms) or to the existence of two or more different crystalline forms that is, of different arrangements of the atoms or molecules in a crystalline array. 

Fluorine is characterized by its extraordinary chemical reactivity— it is the most active of the elements. Non-metals, such as hydrogen, sulfur, iodine, and arsenic, and metalloids, such as silicon, boron, and carbon, combine spontaneously with fluorine, becoming incandescent. All metals are attacked by the gas. The alkali metals and alkaline-earth metals take fire in a stream of the gas at room temperature, whereas the more noble metals react with fluorine when warmed. Fluorine decomposes water, forming hydrogen fluoride and liberating a mixture of oxygen and ozone. 

Oxygen exists in three allotropic forms. Allotropes are forms of an element with different physical and chemical properties. The three allotropes of oxygen are normal oxygen, or diatomic oxygen, or dioxygen nascent, atomic, or monatomic oxygen and ozone, or triatomic oxygen. The three allotropes differ from each other in a number of ways. 

Elemental oxygen, O2, is paramagnetic and contains two unpaired electrons. Oxygen forms ozone (O3), oxides (O ), peroxides (O2 ), and superoxides (O2). The most abundant element in Earth s crust, oxygen is essential for life on Earth. 

Oxygen is element number 8 and the most abundant element in Earth s crust. The pure element exists in two allotropic forms and O3 (ozone), which are both gaseous species under average atmospheric conditions. Diatomic oxygen gas, O, composes 21 percent of the atmosphere and is an essential biological element. Ozone composes a thin layer of the stratosphere and is essential to protecting life on the surface of Earth from otherwise harmful ultraviolet radiation. Unfortunately, in the troposphere, ozone is an air pollutant. 

An allotrope is a single physical and chemical form of an element. Both diatomic oxygen and ozone are aUotropes of the element oxygen. 

Different molecular forms of an element are called allotropes of that element. Thus, oxygen and ozone are allotropic forms of oxygen ... 

Ethylene-acrylic elastomers are highly resistant to the damaging aspects of weather, ie, sun, water, oxygen, and ozone. Vulcanizates have shown little change in tensile properties and no visible signs of surface deterioration after exposure to the elements in Florida for 10 years. Samples imder 20% tensile strain (static) displayed no cracks after one week s exposnre to 100 ppm ozone in air, a concentration 100 times greater than is usually specified in qualifying tests. 

A powerfully oxidizing aUotropic form of the element oxygen. The ozone molecule contains three atoms (O3). Ozone gas is decidedly blue, and both liquid and solid ozone are an opaque blue-black color, similar to that of ink. 

It would seem that the phase rule identification and atomic munber identification do not always point to the same simple substances in the case of aUotropes. If allotropes are thought to differ in respect of how the basic substance (atoms of the same element) is combined with itself, this means that oxygen and ozone are allotropes, although they are different substances in the sense of the phase rule ( 8). 

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