Bases Br0nsted-Lowry theory

Acids and bases are defined in accordance with Br0nsted-Lowry theory in terms of their propensity to donate or accept hydrated protons in aqueous... 

THE PROTOLYSIS OF ACIDS. STRENGTHS OF ACIDS AND BASES It is of interest to examine the processes which take place when an acid is dissolved in a solvent, first of all in water. According to the Br0nsted-Lowry theory this dissolution is accompanied by a protolytic reaction, in which the solvent (water) acts as a base. To elucidate these processes, let us examine what happens if a strong acid (hydrochloric acid) and a weak acid (acetic acid) undergo protolysis. 

INTERPRETATION OF OTHER ACID-BASE REACTIONS WITH THE BR0NSTED-LOWRY THEORY As already outlined, the great advantage of the Brensted-Lowry theory lies in the fact that any type of acid-base reaction can be interpreted with the simple reaction scheme... 

The Br0nsted-Lowry theory expands the definition of acids and bases to allow us to explain n ch more ol solution chemistry. For example, the Brpnsted-Lowry theory allows us to explain why a solution af ammonium nitrate tests acidic and a solution of potassium acetate tests basic. Most of the substances that we cofcider acids in the Arrhenius theory are also acids in the Brpnsted-Lowry theory, and the same is true of bases. Injboth theories, strong acids are those that react completely with water to form ions. Weak acids ionize only slightly. We can now explain this partial ionization as an equilibrium reaction of the weak acid, the ions, and the w ater. A similar statement can be made about weak bases ... 

Identify each of the following terms (a) hydronium ion, (b) Br0nsted-Lowry theory, (c) proton (Brpnsted sense), (d) acid (Brpnsted sense), (e) base (Brpnsted sense), (f) conjugate, (g) strong acid or base, Qi) acid dissociation constant, i) base dissociation constant, (/) autoionization, k) pH, and (Z) K. ... 

Br0nsted-Lowry theory a theory of acids and bases that defines acids as proton donors and bases as proton acceptors. 

In contrast to the Br0nsted-Lowry theory, which emphasizes the proton as the principal species in acid-ba.se reactions, the definition proposed by Lux and extended by Floods describes acid-base behavior in terms of the oxide ion. This acid-base concept was advanced to treat nonprotonic systems which were not amenable to the Br0nsted-Lowry definition. For example, in high-temperature inorganic melts, reactions such as the following take place ... 

The Br0nsted-Lowry theory assumes a transfer of protons from an acid to a base, i.e., conjugate pairs. 

The Br0nsted-Lowry theory conjugate acid-base pairs... 

An even more general theory of acids and bases was given by the American chemist G. N. Lewis in 1923. In this theory, an acid is an electron acceptor and a base is an electron donor. This is a more general theory than the Br0nsted-Lowry theory, because it allows the acid-base classification to be applied to reactions in which neither H (aq) nor OH (aq) play a role, or even to reactions in which there is no solvent. For example, the following are acid-base reactions in the Lewis theory... 

In Chapter 5 we saw that, in terms of the Br0nsted-Lowry theory, acid-base reactions involve proton transfer. Another large and important group of chemical reactions, particularly in aqueous solutions, involves electron transfer these are referred to as oxidation-reduction (or redox) reactions. Redox reactions are involved (1) in photosynthesis, which releases oxygen into the Earth s atmosphere (2) in the combustion of fuels, which is responsible for rising concentrations of atmospheric carbon dioxide (3) in the formation of acid precipitation and (4) in many chemical reactions in Earth sediments. 

The Br0nsted-Lowry theory of acids and bases involves the transfer of protons or hydrogen ions within an aqueous solution. An acid is defined as a molecule or ion that acts as a proton donor and a base is defined as a molecule or ion that acts as a proton acceptor. For example, when hydrogen chloride gas is dissolved in water it reacts to form hydrochloric acid. The following equilibrium is established ... 

Br0nsted-Lowry theory can also be applied to the behaviour of bases in aqueous solution. For example, when ammonia gas is dissolved in water the following chemical equilibrium is established ... 

However, the Lewis theory is more general than the Br0nsted-Lowry theory some reactions are classified as acid-base reactions under the Lewis definitions that are not regarded as acid-base reactions under the Br0nsted-Lowry theory. Therefore the terms Lewis acid and Lewis base are often reserved for species which are Lewis acids and bases, but which are not Br0nsted-Lowry acids and bases. 

The Lewis definition does not associate acidity with any particular element but rather to electronic arrangement. Lewis theory does not falsify Br0nsted-Lowry theory but extends it Brpnsted-Lowry theory is a subset of Lewis theory. All Brpnsted-Lowry bases are Lewis bases and all Brpnsted-Lowry acids are Lewis... 

The Br0nsted-Lowry theory can be applied to solvents other than water. Ammonia, like water, is amphiprotic and can behave as a Br0nsted-Lowry acid or base ... 

The shortcomings of the Arrhenius theory led chemists to seek other explanations for the nature of acids and bases. The Br0nsted-Lowry theory was introduced independently in 1923 by the Danish chemist Johannes Nicolaus Brqnsted and the English chemist Thomas Martin Lowry, stating that any compound that can transfer a proton to any other compound is an acid, and the compound that accepts the proton is a base. Their theory explained the behaviour of all of the acids and bases covered by the Arrhenius theory, but also was able to resolve some of the problems with that theory. That is, they were able to explain why some salts are acidic and basic (due to salt hydrolysis) and why no free protons are found in the solutions of some acids. 

By the Br0nsted-Lowry theory, water can be either an acid or a base. Can water be a Lewis acid A Lewis base Explain. 

Our principal interest in acid-base chemistry is in aqueous solutions, where the Br0nsted-Lowry theory prevails. The balance of this chapter is limited to the proton-transfer concept of acids and bases. 

Bases are much the same in the Lewis theory and in the Brpnsted-Lowry theory, because in the Br0nsted-Lowry theory a base must donate a pair of electrons in order to accept a proton. 

Br0nsted-Lowry theory of acids and bases (Section 3.2A) An acid is a substance that can donate (or lose) a proton a base is a substance that can accept (or remove) a proton. The conjugate acid of a base is the molecule or ion that forms when a base accepts a proton. The conjugate base of an acid is the molecule or ion that forms when an acid loses its proton. 

According to the Br0nsted-Lowry theory, a conjugate acid-base pair consists of molecules or ions related by the loss of one by an acid, and the gain of one by a... 

According to the Br0nsted-Lowry theory, acids are donors and bases are acceptors. 

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