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Mono-Bond Typed Binary Compounds

Binary compounds – chemical substances made from just two chemical elements – are individually structurally simple, yet taken together the materials possess & exhibit a rich set of behaviours. The logical structure & reactivity arguments put forward in the Chemogenesis web book employ binary compounds as examples wherever possible.

Definition of Binary Compound

Dictionary and web definition of a binary is: "A chemical compound composed of only two elements", here, here & here.

However, in this web book we use a slightly different, tighter and local – within Chemogenesis – definition:

Many binary compounds fail our strict one-type-of-strong-chemical-bond requirement. For example, there are literally thousands of hydrocarbons (substances consisting of hydrogen and carbon only) including: methylene, CH2, methane, CH4, ethane, C2H6, ethene, C2H4, ethyne (acetylene), C2H2, benzene, C6H6, toluene, C7H8, polythene, [CH2]n, etc.

But ONLY methylene, CH2, and methane, CH4, possess only one type of strong chemical bond and are the only substances to be considered binary compoundshere.

Water, H–O–H, only has hydrogen-to-oxygen bonds, whereas hydrogen peroxide, H–O–O–H, has hydrogen-to-oxygen and oxygen-to-oxygen bonds.

Likewise, NO and NO2 are mono bond type binaries, whereas N2O3, N2O4 (the dimer of NO2) and N2O5 are not.

The chemical elements as material substances are herewithin the Chemogenesis web book – considered to be special case binaries where the two elements are identical: H2, O2, N2, etc. This definition also holds with bulk elemental materials: lithium, Li, carbon (diamond), C, carbon (graphite), C, silicon, Si, etc... that exist as extended lattice structures rather than forming discrete molecules.

Allotropes | Polymorphs | Particle Size

From the Wikipedia:

"Allotropy, or allotropism, is the property of some chemical elements to be able to take two or more different structural forms that exhibit quite different physical properties and chemical behaviours."

From the Wikipedia:

"Polymorphism is the ability of a solid material to exist in more than one form or crystal structure. Polymorphism can potentially be found in any crystalline material including polymers, minerals, and metals, and is related to allotropy, which refers to elemental solids. Together with polymorphism the complete morphology of a material is described by other variables such as crystal habit, amorphous fraction or crystallographic defects.

The chemistry of a solid substance can be strongly influenced by the particle size.

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Periodicity Binary Compound Synthlet

© Mark R. Leach 1999 –

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