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	Gilbert N. Lewis - Wikipedia, the free encyclopedia
		Lewis was born in Weymouth, Massachusetts as the son of a Dartmouth-graduated lawyer/broker.
		In the so-called Lewis theory of acids and bases, a "Lewis acid" is an electron-pair acceptor and a "Lewis base" is an electron-pair donor.
		Lewis was the first to produce a pure sample of deuterium oxide (heavy water) in 1933.
	en.wikipedia.org /wiki/Gilbert_N._Lewis (758 words)

	Lewis base - Wikipedia, the free encyclopedia
		A Lewis base is any molecule or ion that can form a new coordinate covalent bond, by donating a pair of electrons.
		Lewis bases do not require a hydroxide ion as the electron acceptor.
		When a Lewis acid and Lewis base form a complex ion the Lewis base is always the ligand.
	en.wikipedia.org /wiki/Lewis_base (89 words)

	[No title]
		Lewis contends that he is entitled to a new trial because, notwithstanding his indictment for distribution of at least five grams of cocaine base, the district court instructed the jury that it could find him guilty whether he had distributed cocaine powder or cocaine base.
		Finally, Lewis argues that even if we uphold his conviction he is entitled to a remand for resentencing because the government failed to prove by 2 a preponderance of the evidence that the controlled substance he distributed was cocaine base.
		Lewis asserts that this charge to the jury broadened the indictment and violated his right to be tried only on an indictment returned by the grand jury.
	vls.law.vill.edu /Locator/3d/May1997/97a1591p.txt (2845 words)

	Chapter 16, Section 11 (Site not responding. Last check: 2007-11-06)
		He proposed a definition of acid and base that emphasizes the shared electron pair: A Lewis acid is defined as an electron-pair acceptor, and a Lewis base is defined as an electron-pair donor.
		Everything that is a base in the Brønsted-Lowry sense (a proton acceptor) is also a base in the Lewis sense (an electron-pair donor).
		The process of hydration is a Lewis acid-base interaction in which the metal ion acts as a Lewis acid and the water molecules as Lewis bases.
	cwx.prenhall.com /bookbind/pubbooks/blb/chapter16/medialib/blb1611.html (914 words)

	ChemTeam: The Lewis Theory of Acids and Bases (Site not responding. Last check: 2007-11-06)
		Keep in mind that Bronsted-Lowry, which defines an acid as a proton donor and a base as a proton acceptor, REQUIRES the presence of a solvent, specifically a protic solvent, of which water is the usual example.
		The Lewis definitions of acid and base do not have the constraints that the Bronsted-Lowry theory does and, as we shall see, many more reactions were seen to be acid base in nature using the Lewis definition than when using the Bronsted-Lowry definitions.
		A "Lewis acid" is any atom, ion, or molecule which can accept electrons and a "Lewis base" is any atom, ion, or molecule capable of donating electrons.
	dbhs.wvusd.k12.ca.us /webdocs/AcidBase/Intro-to-Lewis-AcidBase.html (535 words)

	acids and bases. The Columbia Encyclopedia, Sixth Edition. 2001-05 (Site not responding. Last check: 2007-11-06)
		Acids, such as hydrochloric acid, and bases, such as potassium hydroxide, that have a great tendency to dissociate in water are completely ionized in solution; they are called strong acids or strong bases.
		Acids, such as acetic acid, and bases, such as ammonia, that are reluctant to dissociate in water are only partially ionized in solution; they are called weak acids or weak bases.
		It defines an acid as a proton donor and a base as a proton acceptor.
	www.bartleby.com /65/ac/acidsNba.html (827 words)

	Chemical Reactivity
		According to the Brønsted theory, an acid is a proton donor, and a base is a proton acceptor.
		The relative strength of a group of acids (or bases) may be evaluated by measuring the extent of reaction that each group member undergoes with a common base (or acid).
		In its Brønsted acid role the carbocation donates a proton to the base (hydroxide anion), and is converted to a stable neutral molecule having a carbon-carbon double bond.
	www.cem.msu.edu /~reusch/VirtualText/react1.htm (4172 words)

	03-7037 -- U.S. v. Lewis -- 05/18/2004
		In finding Lewis guilty on both counts, the jury specifically found with respect to Count One that Lewis was in possession of more than 50 grams of a mixture or substance containing cocaine base.
		Lewis interprets the reference to "detectable amount" to mean that "[n]o specific amount of cocaine base was ever alleged and/or stated in the indictment." Id.
		Based upon this testimony, the jury reasonably could have found the entire quantity of drugs seized on February 9, 2002, contained cocaine base.
	www.kscourts.org /ca10/cases/2004/05/03-7037.htm (757 words)

	Lewis base -- Facts, Info, and Encyclopedia article (Site not responding. Last check: 2007-11-06)
		A Lewis base is any molecule or ion that can form a new (additional info and facts about coordinate covalent bond) coordinate covalent bond, by donating a pair of electrons.
		A (additional info and facts about nucleophile) nucleophile is a Lewis base.
		When a Lewis acid and Lewis base form a (additional info and facts about complex ion) complex ion the Lewis base is always the (An atom or molecule or radical or ion that forms a complex around a central atom) ligand.
	www.absoluteastronomy.com /encyclopedia/l/le/lewis_base.htm (198 words)

	Ionic Equilibria (Site not responding. Last check: 2007-11-06)
		Their definition was based on the observation that in the neutralization reaction a hydrogen ion, refered to as a proton, was transfered from one substance to another.
		Lewis noted that some compounds that were not acids or bases under the Bronsted-Lowry definition nevertheless reacted in similar ways as Bronsted-Lowry acids and bases.
		Similarly the protonated base, BH, in equilibrium (6) is the
	v.d.singleton.home.att.net /genchem/ionequil.htm (3368 words)

	Lewis Concept of Acids and Bases (Site not responding. Last check: 2007-11-06)
		Lewis developed a theory of acids and bases that is based upon the sharing of electron pairs.
		A Lewis base is a substance that can donate a pair of electrons to another atom to form a new bond.
		All metal cations are potential Lewis acids because their positive charge will readily attract electron pairs and they all have at least on empty orbital.
	erkki.kennesaw.edu /GCII6/gc00012.htm (305 words)

	Chemistry : Chapter 16 : Overview (Site not responding. Last check: 2007-11-06)
		However, substances are generally classified as an acid or base based on the reaction of that substance in (with) water.
		Bases are normally metal hydroxides or organic nitrogen compounds (amines) or ammonia (NH), which is a special case of an amine.
		This is most obvious with the nitrogen bases, where the hydrogen bonded to the nitrogen creates the conjugate acid of the nitrogen base.
	www.wwnorton.com /chemistry/overview/ch16.htm (1874 words)

	United States Patent Application: 0040091772
		Thermally stable electrolytes for Li-ion batteries obtained with the use of Lewis base additives to the electrolytes are disclosed.
		It has been discovered in accordance with the invention that the addition of a Lewis base additive to the non-aqueous electrolyte of a rechargeable Li-ion battery significantly improves the thermal stability of the electrolyte and consequently greatly enhances the cycling efficiency and cycle life of the battery.
		A Lewis base is defined as a chemical compound having unpaired electrons capable of donating them to an electron acceptor compound (or a Lewis acid) such as PF.sub.5.
	appft1.uspto.gov /netacgi/nph-Parser?Sect1=PTO1&Sect2=HITOFF&d=PG01&p=1&u=/netahtml/PTO/srchnum.html&r=1&f=G&l=50&s1="20040091772".PGNR.&OS=DN/20040091772&RS=DN/20040091772 (3456 words)

	[No title] (Site not responding. Last check: 2007-11-06)
		Such Lewis base compounds should be capable of binding to the activator Lewis acid such that at room temperature reactions between the Lewis acid and the transition metal alkyls are inhibited.
		Additionally, the Lewis base may be an independent compound or may comprise part of the ligand framework of the olefin polymerization catalyst.
		The Lewis base group used to complex the halogenated aryl-substituted Lewis acid is a neutral compound having an electron donating moiety in a chemically accessible position so that it can complex with the Lewis acid and satisfies the above-mentioned criteria as to Lewis acid strength.
	www.wipo.int /cgi-pct/guest/getbykey5?KEY=99/64476.991216&ELEMENT_SET=DECL (6224 words)

	Fort Lewis Internet
		The Fort Lewis tradition of donating a Christmas tree to the city of Tacoma continued its 59th year Nov. 8.
		The Fort Lewis Museum houses an impressive collection of military history dating as far back as the 1700's.
		The Youth Fitness Zone is the new teen center for youths in grades 9 to 12.
	www.lewis.army.mil (340 words)

	Lewis Acid-Base Experiment (Site not responding. Last check: 2007-11-06)
		Lewis acids, which are electron pair acceptors, and Lewis bases, which are electron pair donors, react to form adducts in which a coordinate covalent bond is formed.
		The strength of the interaction between a Lewis acid and a Lewis base is controlled by at least two factors, electronic and steric (1).
		Trimethylamine, N(CH, is a Lewis base and because of the electron donating methyl groups, it should be a stronger base than NH when both are compared with a common Lewis acid.
	www.molecules.org /experiments/Coskran/Coskran.html (948 words)

	Outcomes Review Chapter 6 (Site not responding. Last check: 2007-11-06)
		In Lewis acid-base reactions, a nonbonding electron pair on a Lewis base is attracted to a positive center on a Lewis acid and the electrons form a new covalent bond between the two reactants.
		Lewis acid-base reactions also occur between ligands, Lewis bases, and metal ions, Lewis acids, to which the bases bond to form metal ion complexes, many of which are important in biological systems.
		recognize the formation of a metal ion complex between a Lewis base and a metal ion in solution by observations on mixtures of the reactants (or in competitions between the Lewis base and another reactant for the metal ion) and suggest a structure for the complex [Section 6.6].
	www.acs.org /portal/a/c/s/1/acsdisplay.html?DOC=\education\curriculum\genchem_chapt6.html (674 words)

	Three theories of Acids and Alkalis: Arrhenius, Lowry-Bronsted and Lewis. Loreto, Coleraine.
		Bases, such as ammonia produce OH ions in aqueous solution by undergoing a reaction with water.
		Each substance in the base column is converted to its partner in the acid column by the addition of a proton.
		The Lewis definition is useful because it allows us to classify so many substances as acids or bases, and because it provides an understanding of the details of many chemical reactions.
	www.lcc.ukf.net /Chem14/acidalkali.htm (1002 words)

	The Lewis Acid/Base Interaction Matrix
		The previous page showed that there are six quite distinct types of Lewis acid and four quite distinct types types of Lewis base, where distinction is by frontier molecular orbital (FMO) topology.
		In the 1960s, Ralph Pearson suggested that Lewis acids and Lewis bases should be classified as hard, borderline or soft, with the observation that: "Hard [Lewis] acids prefer to complex with hard [Lewis] bases and soft [Lewis] acids with soft [Lewis] bases", the HSAB principle (go here and here for more information).
		Lewis acid and Lewis base types which are rich in congeneric arrays interact to give complex types which are rich in arrays.
	www.meta-synthesis.com /webbook/13_lab-matrix/LAB_matrix.html (1277 words)

	Search Results for Lewis base - Encyclopædia Britannica
		Lewis, G.N. American chemist whose theory of the electron pair fostered understanding of the covalent bond and extended the concept of acids and bases.
		Lewis MacKenzie published an account of his career, Peacekeeper: The Road to Sarajevo, in which he recounted his harrowing experiences in 1992 as chief of staff of the...
		In the reaction of a Lewis acid with a base the essential process is the formation of an adduct in which the two species are joined by a covalent bond; proton transfers are not normally involved.
	www.britannica.com /search?query=Lewis+base (518 words)

	Acids and Bases
		According to this theory, an acid is a "proton donor" and a base is a "proton acceptor."
		Lewis therefore argued that any substance that can act as an electron-pair donor is a Lewis base.
		The flow of electrons from a Lewis base to a Lewis acid is often indicated with a curved arrow.
	chemed.chem.purdue.edu /genchem/topicreview/bp/3organic/acids.html (1649 words)

	Theories of acids and bases
		A base is a proton (hydrogen ion) acceptor.
		The hydroxide ion is a base and water is its conjugate acid.
		On the Lewis theory, any reaction in which the ammonia or water used their lone pairs of electrons to form a co-ordinate bond would be counted as them acting as a base.
	www.chemguide.co.uk /physical/acidbaseeqia/theories.html (1946 words)

	The First Catalytic, Asymmetric -Additions of Isocyanides. Lewis-Base-Catalyzed, Enantioselective Passerini-Type ... (Site not responding. Last check: 2007-11-06)
		The absence of a catalytic, enantioselective variant of this class of reactions is striking, particularly in light of the recent development of chiral Lewis acid catalysts for stereoselective carbon-carbon bond formation with both carbonyl and imine substrates.
		We recognized that the newly introduced concept of Lewis base activation of Lewis acid is ideally suited to address these problems.
		Conclusive evidence of Lewis base catalysis was forthcoming from the use of 5 mol % of the chiral bisphosphoramide 5a,
	pubs.acs.org /cgi-bin/jcen?jacsat/asap/html/ja035410c.html (2117 words)

	Lewis acids and bases
		Note - usually refer to as “Lewis acids” to avoid confusion with BL acids and bases
		Hard Lewis acids tend to combine with hard Lewis bases
		Soft Lewis acids tend to combine with soft Lewis bases
	www.southalabama.edu /chemistry/serafin/ch132/lec19.html (135 words)

	The Lewis Definitions of Acids and Bases (Site not responding. Last check: 2007-11-06)
		A Lewis base is any substance, such as the OH ion, that can donate a pair of nonbonding electrons.
		The principal advantage of the Lewis theory is the way it expands the number of acids and therefore the number of acid-base reactions.
		In the course of this reaction, the water molecule acts as an electron-pair donor, or Lewis base.
	chemed.chem.purdue.edu /genchem/topicreview/bp/ch11/lewis.html (661 words)

	ipedia.com: Base (chemistry) Article (Site not responding. Last check: 2007-11-06)
		Acids and Bases : Acid-base reaction theories pH Self-ionization of water Buffers Systematic_naming Redox reactions Electrochemistry Strong acids Weak acids Weak bases Strong bases A base is a chemica...
		Bases are typically water-soluble and bitter tasting and always have a pH greater than 7 in solution.
		A base is able to take up a proton from an acid or able to give up an unshared pair of electrons to an acid.
	www.ipedia.com /base__chemistry_.html (351 words)

	The Lewis Acid (Site not responding. Last check: 2007-11-06)
		This definition is more general than those we have seen to this point; any Arrhenius acid or base, or any Brønsted-Lowry acid or base can also be viewed as a Lewis acid or base.
		The hydroxide ion donates a pair of electrons for covalent bond formation, thus OH is a Lewis base in this reaction.
		The BF is the Lewis acid and the N(CH is the Lewis base.
	faculty.ssu.edu /~dfrieck/212/rev/acidbase/lewis.htm (224 words)

	Chapter 6 Substitution and Elimination Reactions: SN1, SN2, E1, E2
		Lewis Base : any species with a reactive pair of electrons (donates a pair of electrons in reactions)
		Lewis Acid : species that reacts with a Lewis base (accepts a pair of electrons in reactions)
		Lewis bases that donate electrons in substitution reactions are known as
	www.ipfw.edu /chem/261/261Fall03/261nt02l.htm (512 words)

	Unit 9: Acids and Bases
		The Lewis Acid-Base Model viewed an acid as an electron pair acceptor and the base as a electron-pair donor.
		The Lewis acid accepts this electron from a molecule that has a lone pair of electrons, the Lewis Base.
		The real value of the Lewis model for acids however is that it covers many reations that do not involve Bronsted-Lowry Acids, such as the gas-phase reaction between boron trifluoride and ammonia.
	www.angelfire.com /apes/bs4eva/Unit9b.html (257 words)

	Acid-Base Theories
		Acids may be cations, neutral molecules, or anions, while bases may be anions or neutral molecules.
		Lewis suggested his theory in a 1923 book "Thermodynamics and the Free Energy of Chemical Substances" and fully developed the theory in 1938.
		Lewis expands acid/base reactions to include many substances without H in formula.
	web.fccj.org /~ethall/acidbase/acidbase.htm (529 words)

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