Bases Arrhenius acid

Arrhenius acid, Bransted-Lowry acid Arrhenius acid, Bransted-Lowry acid Arrhenius base, Bransted-Lowry base Arrhenius acid, Bransted-Lowry acid amphoteric hydroxide (can act as either an acid or base)... 

Naming Acids and Bases Operational Definitions of Acids and Bases Conceptual Definition of Acids and Bases Arrhenius Acids and Bases... 

Arrhenius acid Species that, upon addition to water, increases [H+], 86 Arrhenius base Species that, upon addition to water, increases [OH-], 86 Arrhenius equation Equation that expresses the temperature dependence of the rate constant In k2/ki = a(l/Ti — 1 IT2)IR, 302-305... 

These compounds are called Arrhenius acids and bases. For instance, HCI is an Arrhenius acid, because it releases a hydrogen ion, H+ (a proton), when it dissolves... 

Recall that an Arrhenius acid is a compound that produces hydronium ions in water and an Arrhenius base is a compound that produces hydroxide ions in water. 

The first substantial constitutive concept of acid and bases came only in 1887 when Arrhenius applied the theory of electrolytic dissociation to acids and bases. An acid was defined as a substance that dissociated to hydrogen ions and anions in water (Day Selbin, 1969). For the first time, a base was defined in terms other than that of an antiacid and was regarded as a substance that dissociated in water into hydroxyl ions and cations. The reaction between an acid and a base was simply the combination of hydrogen and hydroxyl ions to form water. 

Thus, acids and bases are defined as aqueous solutions of substances and not as the substances themselves. It follows that ionization is a necessary characteristic of Arrhenius acids and bases. Another restriction of this definition is that acid-base behaviour is not recognized in non-aqueous solution. 

According to the Arrhenius theory of acids and bases, the acidic species in water is the solvated proton (which we write as H30+). This shows that the acidic species is the cation characteristic of the solvent. In water, the basic species is the anion characteristic of the solvent, OH-. By extending the Arrhenius definitions of acid and base to liquid ammonia, it becomes apparent from Eq. (10.3) that the acidic species is NH4+ and the basic species is Nl I,. It is apparent that any substance that leads to an increase in the concentration of NH4+ is an acid in liquid ammonia. A substance that leads to an increase in concentration of NH2- is a base in liquid ammonia. For other solvents, autoionization (if it occurs) leads to different ions, but in each case presumed ionization leads to a cation and an anion. Generalization of the nature of the acidic and basic species leads to the idea that in a solvent, the cation characteristic of the solvent is the acidic species and the anion characteristic of the solvent is the basic species. This is known as the solvent concept. Neutralization can be considered as the reaction of the cation and anion from the solvent. For example, the cation and anion react to produce unionized solvent ... 

Our goal in this chapter is to help you understand the equilibrium systems involving acids and bases. If you don t recall the Arrhenius acid-base theory, refer to Chapter 4 on Aqueous Solutions. You will learn a couple of other acid-base theories, the concept of pH, and will apply those basic equilibrium techniques we covered in Chapter 14 to acid-base systems. In addition, you will need to be familiar with the log and 10 functions of your calculator. And, as usual, in order to do well you must Practice, Practice, Practice. 

The Arrhenius theory explains acid-base reactions as a combination of H (aq) and OH (aq). It provides insight into the heat of neutralization for the reaction between a strong acid and a strong base. (Strong acids and bases dissociate completely into ions in solution.) For example, consider the following reaction. 

H (aq) Cl (aq) hJa (aq) + OH (aq) Fla (aq) "t" Cl (aq) "t" H20(r) AH = —56 kJ Subtracting spectator ions from both sides, the net ionic equation is H+(aq) -I- OH (aq) H20(f) AH = -56 kJ Different combinations of strong Arrhenius acids and bases react with the same exothermic result. Measurements always show the release of 56 kJ of energy per mole of water formed. This makes sense, because the net ionic equation is the same regardless of the specific neutralization reaction that occurs. 

S. A. Arrhenius defined an acid as any hydrogen-containing species able to release protons and a base as any species able to form hydroxide ions [71]. The aqueous acid-base reaction is the reaction between hydrogen ions and hydroxide ions with water formation. The ions accompanying the hydrogen and hydroxide ions form a salt, so the overall Arrhenius acid-base reaction can be written ... 

Arrhenius acid—any substance that ionizes when it dissoives in water to give the H ion. Arrhenius base—any substance that ionizes when it dissoives in water to give the OH" ion. 1 point for correct answer. 

Each of the three definitions expands our concept of acids and bases. Arrhenius basic definition is adequate for understanding many of the properties of acids and bases. It is important to recognize, though, that acids and bases are not fixed labels that can be applied to a substance. Bronsted-Lowry and Lewis showed that acid-base characteristics are dependent on the reactions that take place between substances. A... 

The above reaction depicts water as an Arrhenius acid and base. Treating water in terms of the Bronsted-Lowry theory, a more appropriate reaction would be... 

Arrhenius subsequently expanded his theories to form one of the most widely used and straightforward definitions of acids and bases. Arrhenius said that acids are substances that form hydrogen (H+) ions when they dissociate in water, while bases cire substances that form hydroxide (OH ) ions when they dissociate in water. 

For Arrhenius acids, remember to track the movement of H" and OH ions. If the reaction yields an OH product, the substance is a base, whereas an H+ product reveals that the substance is an acid. 

In 1884, Swedish chemist Svante Arrhenius defined acids as compounds that produce H" " ions in aqueous solutions, and bases as compounds that produce OH ions in aqueous solutions. For example, HCl and HNO3 are Arrhenius acids. 

The Arrhenius acid-base theory is insufficient to explain the acidic or basic properties of some substances, such as SO2 and NH3, since these don t have H" and OH ions in their structures. For these molecules, another theory must be applied, since the Arrhenius acid-base theory can only be applied to aqueous solutions. 

Pure water can be considered both an acid and a base because water dissociates slightly to produce hydrogen and hydroxide ions H2Offi < > H+(a(i) + OH (a. This equation depicts water as an Arrhenius acid and base. An Arrhenius acid is any substance which when dissolved in water produces hydrogen ions, H+. An Arrhenius base is a substance that produces hydroxide ions, OH. Treating water in terms of the Brans ted-Lowry theory, a more appropri-... 

Antiferromagnetism, 467-468 Aprotic solvents, 369-373 Aqueous solvents, and non-aqueous solvents. 359-386 Arachno structures, 798-800, 807 Aragonite, 98, 953 Arene complexes, 681-683 Arrhenius acid-base definition, 319... 

We shall call such substances Arrhenius acids and bases. For instance, HC1 is an Arrhenius acid, because it releases a hydrogen ion, H+ (a proton), when it dissolves in water CH4 is not an Arrhenius acid, because it does not release hydrogen ions in water. Sodium hydroxide is an Arrhenius base because OH ions go into solution when it dissolves ... 

Thus far we ve been using the Arrhenius theory of acids and bases (Section 4.5). According to Arrhenius, acids are substances that dissociate in water to produce hydrogen ions (H + ), and bases are substances that dissociate in water to yield hydroxide ions (OH-). Thus, HC1 and H2SO4 are acids, and NaOH and Ba(OH)o are bases. 

The effect of temperature satisfies the Arrhenius relationship where the applicable range is relatively small because of low and high temperature effects. The effect of extreme pH values is related to the nature of enzymatic proteins as polyvalent acids and bases, with acid and basic groups (hydrophilic) concentrated on the outside of the protein. Finally, mechanical forces such as surface tension and shear can affect enzyme activity by disturbing the shape of the enzyme molecules. Since the shape of the active site of the enzyme is constructed to correspond to the shape of the substrate, small alteration in the structure can severely affect enzyme activity. Reactor s stirrer speed, flowrate, and foaming must be controlled to maintain the productivity of the enzyme. Consequently, during experimental investigations of the kinetics enzyme catalyzed reactions, temperature, shear, and pH are carefully controlled the last by use of buffered solutions. 

A Lewis base transfers an electron pair to a Lewis acid. A Bronsted acid transfers a proton to a Bnansted base. These exist in conjugate pairs at equilibrium. In an Arrhenius base, the proton acceptor (electron pair donor) is OH-. All Arrhenius acids/bases are Bronsted acids/bases and all Bransted acids/bases are Lewis acids/bases. Each definition contains a subset of the one that comes after it. 

C Choice A is the definition of a strong acid, choice B is the definition of a Lewis acid, and choice D is the definition of an Arrhenius acid. By definition, all Arrhenius bases form OH- ions in water, and all Bronsted bases are proton acceptors. But not all Bronsted bases use OH- as a proton acceptor. NH3 is a Bronsted base for example. 

Given the desire for covalent stability noted above, we must also be wary of protic ionic liquids in general. These species can be written as the product of the reaction of an Arrhenius acid and a base... 

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