A chemical compound (or just compound if used in the context of chemistry) is an entity consisting of two or more atoms, at least two from different elements, which associate via chemical bonds. There are four types of compounds, depending on how the constituent atoms are held together: molecules held together by covalent bonds, salts held together by ionic bonds, intermetallic compounds held together by metallic bonds, and certain complexes held together by coordinate covalent bonds. Many chemical compounds have a unique numerical identifier assigned by the Chemical Abstracts Service (CAS): its CAS number.
A chemical formula is a way of expressing information about the proportions of atoms that constitute a particular chemical compound, using the standard abbreviations for the chemical elements, and subscripts to indicate the number of atoms involved. For example, water is composed of two hydrogen atoms bonded to one oxygen atom: the chemical formula is HO.
A compound can be converted to a different chemical composition by interaction with a second chemical compound via a chemical reaction. In this process, bonds between atoms are broken in both of the interacting compounds, and then bonds are reformed so that new associations are made between atoms. Schematically, this reaction could be described as AB + CD --> AC + BD, where A, B, C, and D are each unique atoms; and AB, CD, AC, and BD are each unique compounds.
A chemical element bonded to an identical chemical element is not a chemical compound since only one element, not two different elements, is involved. Examples are the diatomic molecule hydrogen (H) and the polyatomic molecule sulfur (S).
n. 1 (context chemistry English) Any substance formed by the union of two or more chemical elements in a fixed ratio, the union being a chemical bond. 2 (context informal proscribed English) Any single substance, either compound or element
n. (chemistry) a substance formed by chemical union of two or more elements or ingredients in definite proportion by weight [syn: compound]
Usage examples of "chemical compound".
It does the things epinephrine does, as one might expect of a chemical compound that is virtually the twin of epinephrine.
The odds were good to excellent that the chemical compound Gunn had discovered as the cause of the exploding red tide was filtering out of the solar detoxification plant.
The first distinction was between a chemical compound and a mixture.
Therefore, having before me only a hexagon, I would think that the Senders meant a molecule of a chemical compound, one constructed of six atoms or of six groups of atoms.
All of his men carried tiny particles of a chemical compound, a chalk for writing, which left a mark entirely invisible to the unaided eye, but which the ultra-violet light brought out.
The proper proportions of the fertilizer (which was mainly an ammonia-based chemical compound) and the diesel fuel came from a book.
Six of them will be water mixed with a tiny amount of a chemical compound which we call Lot Six.
But the chemical compound shells of the bullets, dissolving harmlessly in the human body, and even cauterizing their own wounds, were a product of Doc Savage’.
They were ordinary whales, but in a sense, they were all ill - ill because Hezemiah Law had been feeding them a chemical compound which he had spent most of his life in concocting.
Tom tuned the transmitters to repel the chemical compound which Mr.
It was cyano-azethylene, the most complicated chemical compound that it has so far been possible to demonstrate in interstellar space.
Soap is a chemical compound formed when the metal component of the lye, sodium or potassium binds with a free fatty acid and loosely attaches itself to a methyl or ethyl ester in the bio-diesel.
So the Space Patrol set up a great manufactory for a new chemical compound on a planetoid which could be abandoned, afterward, without regret.