A Lewis acid (LA) can accept a pair of electrons and form a coordinate covalent bond. In Computer science, ACID ( Atomicity Consistency Isolation Durability) is a set of properties that guarantee that Database transactions are In Chemistry, a base is most commonly thought of as an aqueous substance that can accept Protons This refers to the Brønsted-Lowry theory of acids and Acid-base extraction is a procedure using sequential Liquid-liquid extractions to purify Acids and bases from mixtures based on their chemical properties Acid-base homeostasis is the part of Human homeostasis concerning the proper balance between Acids and bases, in other words the PH. An acidity function is a measure of the Acidity of a medium or solvent system usually expressed in terms of its ability to donate protons to (or accept protons from a For an individual weak acid or weak base component see Buffering agent. pH is the measure of the acidity or alkalinity of a Solution. The proton affinity, E pa of a Anion or of a neutral Atom or Molecule is a measure of its gas-phase basicity. The self-ionization of water (also autoionization of water, and autodissociation of water) is the chemical reaction in which two water molecules react to produce a In Computer science, ACID ( Atomicity Consistency Isolation Durability) is a set of properties that guarantee that Database transactions are A mineral acid is an Acid derived by Chemical reaction from inorganic Minerals as opposed to Organic acids These have Hydrogen An organic acid is an Organic compound with Acidic properties A Strong acid is an Acid that Ionizes completely in an Aqueous solution (not in the case of Sulfuric acid as it is diprotic A superacid is an Acid with an Acidity greater than that of 100% Sulfuric acid, which has a Hammett acidity function ( H 0 A weak acid is an Acid that does not completely donate all of its hydrogens when dissolved in water In Chemistry, a base is most commonly thought of as an aqueous substance that can accept Protons This refers to the Brønsted-Lowry theory of acids and An organic base is an Organic compound which acts as a base. Organic bases are usually but not always proton acceptors In Chemistry, a base is most commonly thought of as an aqueous substance that can accept Protons This refers to the Brønsted-Lowry theory of acids and In Chemistry, a superbase is an extremely strong base. There is no commonly accepted definition for what qualifies as a superbase but most chemists would accept As the name suggests a non-nucleophilic base is an organic base that is a very Strong base but at the same time a poor Nucleophile. In chemistry a weak base is a Chemical base that does not Ionize fully in an Aqueous solution. The electron is a fundamental Subatomic particle that was identified and assigned the negative charge in 1897 by J A coordinate covalent bond (formerly also known as dative bond) is a description of Covalent bonding between two atoms in which both electrons shared in the bond come The Lewis acid and Lewis base theory, named after the American chemist Gilbert Lewis, is one of several acid-base reaction theories. The United States of America —commonly referred to as the A chemist is a Scientist trained in the Science of Chemistry. Gilbert Newton Lewis ( October 23, 1875 - March 23, 1946) was a famous American physical chemist known for the discovery Therefore the term acid, itself, is ambiguous; it should always be clarified as being a Lewis acid or a Brønsted-Lowry acid. In Computer science, ACID ( Atomicity Consistency Isolation Durability) is a set of properties that guarantee that Database transactions are

An electrophile or electron acceptor is a Lewis acid. In Chemistry, an electrophile (literally electron-lover) is a Reagent attracted to Electrons that participates in a chemical reaction by accepting A Lewis acid usually has a low-energy LUMO, which interacts with the HOMO of the Lewis base. HOMO and LUMO are Acronyms for highest occupied Molecular orbital and lowest unoccupied Molecular orbital, respectively HOMO and LUMO are Acronyms for highest occupied Molecular orbital and lowest unoccupied Molecular orbital, respectively Unlike a Brønsted-Lowry acid, which always transfers a hydrogen ion (H⁺), a Lewis acid can be any electrophile (including H⁺). Hydrogen (ˈhaɪdrədʒən is the Chemical element with Atomic number 1 An ion is an Atom or Molecule which has lost or gained one or more Valence electrons giving it a positive or negative electrical charge Although all Brønsted-Lowry acids are Lewis acids, in common usage the term Lewis acid is often reserved for those Lewis acids which are not Brønsted-Lowry acids.

The reactivity of Lewis acids can be judged from the Hard-Soft Acid-Base concept. The HSAB concept is an Acronym for 'hard and soft Acids and bases. There is no universally valid description of Lewis acid strength, because Lewis acid strength depends on the specific Lewis base. One model ^[1] has predicted Lewis acid strength based on a computational model of gas-phase affinity for fluoride, and out of a selection of common isolable Lewis acids they found that SbF₅ had the strongest fluoride affinity. Fluoride is the reduced form of Fluorine. Both organic and Inorganic compounds containing the element fluorine are considered fluorides Antimony pentafluoride is the Chemical compound with the formula Sb[[Fluorine F]]5 Fluoride is a "hard" Lewis base; chloride and "softer" Lewis bases are very difficult to study because of limitations of the computational methods, and Lewis acidity in solution suffers from the same restriction. The chloride Ion is formed when the element Chlorine picks up one Electron to form an Anion (negatively-charged ion Cl&minus In Chemistry, a solution is a Homogeneous Mixture composed of two or more substances ^[2]

Some common Lewis acids include aluminium chloride, iron(III) chloride, boron trifluoride, niobium pentachloride and the lanthanide triflates such as ytterbium(III) triflate. Aluminium chloride (AlCl3 is a compound of Aluminium and Chlorine. Iron chloride redirects here For Iron(II chloride see Iron(II chloride. Boron trifluoride is the Chemical compound with the formula BF3 Niobium(V chloride, also known as niobium pentachloride, is a yellow crystalline solid often used as a starting material in Niobium chemistry Lanthanide triflates are Triflate salts of the Lanthanide family with many uses in Organic chemistry as Lewis acid Catalysts The catalysts

Lewis acids may be corrosive. Zinc chloride, which is corrosive, particularly towards cellulose (paper and cotton), is a notable example of Lewis acidity itself causing a corrosive effect. Zinc chloride is the name of Chemical compound with the formula Zn[[chlorine Cl]]2 and its hydrates As water is Lewis basic, common Lewis acids react rapidly with water to give hydrates, which are Brønsted acidic. Water is a common Chemical substance that is essential for the survival of all known forms of Life. Thus, solutions of many common Lewis acids are also Brønsted acidic. Hydrates have strong chemical bonding between the Lewis acid and water, and it is usually not possible to "dry" them, i. e. the hydrate forms a separate chemical compound. For example, attempted drying of a metal chloride gives vapors of hydrogen chloride and metal oxychloride.

Contents 1 Ate complexes 2 References 3 Further reading 4 See also

Ate complexes

An ate complex is a salt formed by reaction of a Lewis acid with a base whereby the central atom increases its valence ^[3]. Salt is a Dietary mineral composed primarily of Sodium chloride that is essential for Animal life but toxic to most land plants In Chemistry, valence, also known as valency or valency number, is a measure of the number of Chemical bonds formed by the Atoms Often in chemical nomenclature the phrase ate is suffixed to the element in question. In Grammar, a suffix (also postfix, ending) is an Affix which is placed at the end of a word For example, the ate complex of a boron compound is called a borate. Boron (ˈbɔərɒn is a Chemical element with Atomic number 5 and the chemical symbol B. Borates in Chemistry are Chemical compounds containing Boron bonded to three Oxygen atoms written as B(OR3 Thus trimethylborane and methyllithium react to form the ate compound Me₄B^-Li⁺. Methyllithium is an Organolithium reagent with the empirical formula CH3Li This concept was introduced by Georg Wittig in 1958 ^[4]. Georg Wittig ( June 16, 1897 &ndash August 26 1987) was a German Chemist who reported a method for synthesis of Similarly Lewis bases form onium salts. Onium compounds are Cations derived by the Protonation of mononuclear parent Hydrides of elements of the nitrogen family (Group 15 chalcogen family (Group

References

Further reading

• The Lewis acid-base concepts : an overview, 1980, ISBN 0471039020
• Selectivities in Lewis acid promoted reactions, 1989, ISBN 0792304527
• Lewis acid reagents : a practical approach, 1999, ISBN 0198500998

See also

• Acid-base reaction
• Base (chemistry)
• Brønsted-Lowry acid-base theory
• Lewis base

A digital object identifier ( DOI) is a permanent identifier given to an Electronic document. Year 1980 ( MCMLXXX) was a Leap year starting on Tuesday (link displays the 1980 Gregorian calendar) Year 1989 ( MCMLXXXIX) was a Common year starting on Sunday (link displays 1989 Gregorian calendar) Year 1999 ( MCMXCIX) was a Common year starting on Friday (link will display full 1999 Gregorian calendar) In Chemistry, a base is most commonly thought of as an aqueous substance that can accept Protons This refers to the Brønsted-Lowry theory of acids and

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