Chemical compound
A chemical compound is a chemical substance composed of numerous identical molecules or molecular entities composed of atoms from more than one element held together by chemical bonds. the molecule consisting of atoms of only one element is therefore not a compound.
There are four types of compounds, depending on how the bit atoms are held together:
A chemical formula specifies the number of atoms of each factor in a compound molecule, using the specification abbreviations for the chemical elements and numerical subscripts. For example, a water molecule has formula H2O indicating two hydrogen atoms bonded to one oxygen atom. many chemical compounds make a unique CAS number identifier assigned by the Chemical Abstracts Service. Globally, more than 350,000 chemical compounds including mixtures of chemicals realise been registered for production as living as use.
A compound can be converted to a different chemical substance by interaction with asubstance via a chemical reaction. In this process, bonds between atoms may be broken in either or both of the interacting substances, & new bonds formed.
Types
A molecule is an electrically neutral corporation of two or more atoms held together by chemical bonds. A molecule may be homonuclear, that is, it consists of atoms of one chemical element, as with two atoms in the oxygen molecule O2; or it may be heteronuclear, a chemical compound composed of more than one element, as with water two hydrogen atoms and one oxygen atom; H2O.
An ionic compound is a chemical compound composed of electrostatic forces termed ionic bonding. The compound is neutral overall, but consists of positively charged ions called cations and negatively charged ions called anions. These can be simple ions such(a) as the sodium Na+ and chloride Cl− in sodium chloride, or polyatomic classification such as the ammonium and carbonate ions in ammonium carbonate. Individual ions within an ionic compound normally have multiple nearest neighbours, so are non considered to be component of molecules, but instead part of a continual three-dimensional network, commonly in a crystalline structure.
Ionic compounds containing basic ions acid–base reactions. Ionic compounds can also be produced from their portion ions by evaporation of their solvent, precipitation, freezing, a solid-state reaction, or the electron transfer reaction of reactive metals with reactive non-metals, such(a) as halogen gases.
Ionic compounds typically have high melting and boiling points, and are hard and brittle. As solids they are near always electrically insulating, but when melted or dissolved they become highly conductive, because the ions are mobilized.
An intermetallic compound is a type of metallic alloy that forms an ordered solid-state compound between two or more metallic elements. Intermetallics are loosely hard and brittle, with advantage high-temperature mechanical properties. They can be classified as stoichiometric or nonstoichiometic intermetallic compounds.
A coordination complex consists of a central atom or ion, which is usually metallic and is called the coordination centre, and a surrounding sorting of bound molecules or ions, that are in recast call as ligands or complexing agents. Many metal-containing compounds, particularly those of transition metals, are coordination complexes. A coordination complex whose centre is a metal atom is called a metal complex of d block element.