Page 192 - Academic Press Encyclopedia of Physical Science and Technology 3rd InOrganic Chemistry

P1: GSS Final Pages Qu: 00, 00, 00, 00
Encyclopedia of Physical Science and Technology EN009F-398 July 6, 2001 20:34

Main Group Elements

Russell L. Rasmussen, retired Joseph G. Morse
Wayne State College Karen W. Morse
Utah State University

I. Boron
II. Aluminum, Gallium, Indium, and Thallium
III. Carbon
IV. Silicon
V. Germanium, Tin, and Lead
VI. Multiple-Bond Compounds
VII. Nitrogen
VIII. Phosphorus
IX. Arsenic, Antimony, and Bismuth
X. Oxygen
XI. Sulfur
XII. Selenium and Tellurium

GLOSSARY rule. The following structure is electron deficient, hav-
ing six rather than eight electrons surrounding boron:
Anisotropic Characterized by having physical properties
F F
that vary along different axes, for example, the electri-
B B
cal conductivity of graphite. F F F F
Concatenate To link together to form chains of like
atoms. Electronegativity Measure of the relative attraction of
Diamagnetism Repulsion of a chemical species by a an atom for the electrons in a bond. Nonmetals have
magnetic field, an indication that all electrons are high electronegativity values; metals tend to have low
paired. values.
EC (enzyme code number) Specific code number as- Hydrogenbonding Intermolecularforcearisingfromthe
signed to an enzyme to indicate the type of reaction it attraction of a hydrogen atom covalently bonded to a
catalyzes and the type of molecule (substrate) it acts on. highly electronegative atom (fluorine, oxygen, or ni-
Electron deficient Characterized by an insufficiency of trogen) for a second nearby electronegative atom, as
electrons around the central atom relative to the octet shown below for hydrogen bonding between water

1