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In 1923, physical chemists Johannes Nicolaus Brønsted in Denmark and Thomas Martin Lowry in England both independently proposed the theory named after them. [5] [6] [7] In the Brønsted–Lowry theory acids and bases are defined by the way they react with each other, generalising them. This is best illustrated by an equilibrium equation.
A Lewis base is also a Brønsted–Lowry base, but a Lewis acid does not need to be a Brønsted–Lowry acid. The classification into hard and soft acids and bases ( HSAB theory ) followed in 1963. The strength of Lewis acid-base interactions, as measured by the standard enthalpy of formation of an adduct can be predicted by the Drago–Wayland ...
In chemistry, an acid–base reaction is a chemical reaction that occurs between an acid and a base.It can be used to determine pH via titration.Several theoretical frameworks provide alternative conceptions of the reaction mechanisms and their application in solving related problems; these are called the acid–base theories, for example, Brønsted–Lowry acid–base theory.
In acid catalysis and base catalysis, a chemical reaction is catalyzed by an acid or a base. By Brønsted–Lowry acid–base theory, the acid is the proton (hydrogen ion, H +) donor and the base is the proton acceptor. Typical reactions catalyzed by proton transfer are esterifications and aldol reactions.
In the above example, acetate is the base of the reverse reaction and hydronium ion is the acid. One hallmark of the Brønsted–Lowry theory in contrast to Arrhenius theory is that it does not require an acid to dissociate. The essence of Brønsted–Lowry theory is that an acid only exists as such in relation to a base, and vice versa.
A plot of the common logarithm of the reaction rate constant k versus the logarithm of the ionization constant K a for a series of acids (for example a group of substituted phenols or carboxylic acids) gives a straight line with slope α and intercept C. The Brønsted equation is a free-energy relationship.
According to the Brønsted-Lowry theory of acids and bases, acids are proton donors and bases are proton acceptors. [4] An amphiprotic molecule (or ion) can either donate or accept a proton , thus acting either as an acid or a base .
For example, at least twenty ternary oxide phases are formed between strontium and vanadium including SrV 2 O 6, Sr 2 V 2 O 5, SrVO 3 and Sr 2 VO 4. [7] The structural chemistry of ternary and more complex oxides is an extensive subject, but there are a few structures that are widely adopted by ternary oxides, such as the perovskite structure.