Nonmetals - Key terms



ALLOTROPES:

Different versions of the same element, distinguished by molecular structure.

DIATOMIC:

A term describing an element that exists as molecules composed of two atoms. This is in contrast to monatomic elements.

ELECTROLYSIS:

The use of an electric current to cause a chemical reaction.

HALOGENS:

Group 7 of the periodic table of elements, with valence electron configurations of ns 2 np 5 . In contrast to the noble gases, the halogens are known for high levels of reactivity.

ION:

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

ISOTOPES:

Atoms that have an equal number of protons, and hence are of the same element, but differ in their number of neutrons. This results in a difference ofmass. Isotopes may be either stable or unstable. The unstable type, known as radioisotopes, are radioactive.

METALS:

Elements that are lustrous or shiny in appearance; malleable, meaning that they can be molded into different shapes without breaking; and excellent conductors of heat and electricity. Metals, which constitute the vast majority of all elements, tend to form positive ions by losing electrons.

MONATOMIC:

A term describing an element that exists as single atoms. This in contrast to diatomic elements.

NOBLE GASES:

Group 8 of the periodic table of elements, all of whom (with the exception of helium) have valence electron configurations of ns 2 np 6 . The noble gases are noted for their extreme lack of reactivity—in other words, they tend not to react to, or bond with, other elements.

NONMETALS:

Elements that have a dull appearance; are not malleable; are poor conductors of heat and electricity; and tend to gain electrons to form negative ions. They are thus opposite of metals in most regards, as befits their name. In addition to hydrogen, in Group 1 of the periodic table, the other 18 nonmetals occupy the upper right-hand side of the chart. They include the noble gases, halogens, and seven "orphan" elements: boron, carbon, nitrogen, oxygen, phosphorus, sulfur, and selenium.

ORBITAL:

A pattern of probabilities regarding the position of an electron for anatom in a particular energy state. The higher the principal energy level, the more complex the pattern of orbitals.

RADIOACTIVITY:

A term describing a phenomenon whereby certain isotopes known as radioisotopes are subject to a form of decay brought about by the emission of high-energy particles. "Decay" does not mean that the isotope "rots"; rather, it decays to form another isotope until eventually (though this may take a long time), it becomes stable.

REACTIVITY:

The tendency for bonds between atoms or molecules to be made or broken in such a way that materials aretransformed.

SHELL:

The orbital pattern of the valence electrons at the outside of an atom.

VALENCE ELECTRONS:

Electrons that occupy the highest principal energy level in an atom. These are the electrons involved in chemical bonding.

Also read article about Nonmetals from Wikipedia

User Contributions:

Comment about this article, ask questions, or add new information about this topic: