Compounds - Key terms





ACID:

An inorganic compound that, when dissolved in water, produces positive ions—that is, cations—of hydrogen, designated symbolically as H + ions. (This is just one definition; see Acids and Bases; Acid-Base Reactions for more.)

ANION:

The negatively charged ion that results when an atom gains one or more electrons. The word is pronounced "AN-ie-un."

BASE:

An inorganic compound that produces negative hydroxide ions when it is dissolved in water. These anions are designated by the symbol OH . (This is just one definition; see Acids and Bases; Acid-Base Reactions for more.)

BINARY COMPOUND:

A compound that contains just two elements. For the purposes of establishing compoundnames, binary compounds are divided into Type I, Type II, and Type III.

CATION:

The positively charged ion that results when an atom loses one or more electrons. The word "cation" is pronounced "KAT-ie-un."

CHEMICAL BONDING:

The joining, through electromagnetic force, of atoms representing different elements.

COMPOUND:

A substance made up of atoms of more than one element, which are chemically bonded and usually joined inmolecules. The composition of a compound is always the same, unless it is changed chemically.

COORDINATION COMPOUNDS:

Inorganic compounds formed when one or more ions or molecules contribute both electrons necessary for a bonding pair in order to bond with a metallic ion or atom.

ELECTRON:

A negatively charged particle in an atom.

INORGANIC COMPOUND:

For the most part, inorganic compounds are anycompounds that do not contain carbon. However, carbonates and carbon oxides are also inorganic compounds. Compare with organic compounds.

ION:

An atom or group of atoms that has lost or gained one or more electrons, and thus has a net electric charge.

IONIC BONDING:

A form of chemical bonding that results from attractions between ions with opposite electric charges.

IONIC COMPOUND:

A compound in which ions are present. Ionic compounds contain at least one metal joined to another element by an ionic bond.

ISOMERS:

Substances which have the same chemical formula, but which have different chemical properties due to differences in the arrangement of atoms.

MIXTURE:

A substance in which elements are not chemically bonded, and in which the composition is variable. A mixture is distinguished from a compound.

ORGANIC COMPOUND:

Generallyspeaking, a compound containing carbon. The only exceptions are the carbonates (for example, calcium carbonate or limestone) and oxides, such as carbon dioxide.

OXIDE:

An inorganic compound in which the only negatively charged ion is anoxygen.

SALT:

An inorganic compound formed by the reaction of an acid with a base. Generally speaking, a salt is a combination of a metal and a nonmetal, and it can contain ions of any element but hydrogen.

TYPE I BINARY COMPOUNDS:

Ionic compounds involving a metal that always forms a cation of a certain electriccharge.

TYPE II BINARY COMPOUNDS:

Ionic compounds involving a metal (typically a transition metal) that forms cations with differing charges.

TYPE III BINARY COMPOUNDS:

Compounds containing only nonmetals.

VALENCE ELECTRONS:

Electrons that occupy the highest energy levels in anatom. These are the only electrons involved in chemical bonding.