Hydroxides acid-base neutralization reactions

In an acid-base neutralization reaction, the hydronium (hydrogen) ions of the acidic solution react with the hydroxide ions in the basic solution. The reaction may be shown by this equation. 

Most indigestion tablets are made of aluminium or magnesium hydroxides. The hydroxide in the tablet removes the excess stomach acid via a simple acid-base neutralization reaction ... 

J.6 Determine the salt that is produced from the acid-base neutralization reaction between (a) potassium hydroxide and acetic acid, CH3COOH (b) ammonia and hydroiodic acid (c) barium hydroxide and sulfuric acid (both H atoms react) (d) sodium hydroxide and hydrocyanic acid, HCN. Write the full ionic equation for each reaction. 

Acid-base neutralization reactions are processes in which an acid reacts with a base to yield water plus an ionic compound called a salt. You might recall from Section 2.9 that we defined acids as compounds that produce H+ ions when dissolved in water and bases as compounds that produce OH- ions when dissolved in water. Thus, the driving force behind a neutralization reaction is the production of the stable covalent water molecule by removal of H + and OH- ions from solution. The reaction between hydrochloric acid and aqueous sodium hydroxide to yield water plus aqueous sodium chloride is a typical example ... 

According to Chapter 11, an acid is a substance that upon dissolving in water increases the concentration of hydronium (H30 ) ions above the value found in pure water, and a base is a substance that increases the concentration of hydroxide (OH ) ions above its value in pure water. Despite the careful language, it is commonplace to view acids and bases as substances that dissociate to give protons (which upon hydration become hydronium ions) and hydroxide ions, respectively. If the dissociation is complete, we can easily calculate the concentration of hydronium and hydroxide ions in the solution and then calculate the yield of acid-base neutralization reactions, and acid-base titrations, by the methods of stoichiometry in solution. But experience shows that many acid-base reactions do not go to completion. So, to predict the amount (or concentration) of... 

They occur not only when a precipitate is formed, but also when an insoluble gas or a weak electrolyte is formed. An acid-base neutralization reaction between sodium hydroxide and hydrochloric acid is an example. 

The salt potassium bromide forms in the acid-base neutralization reaction between hydrobromic acid and potassium hydroxide. 

Most of the observed extra power density for the mixed media configuration is supplied by the electrochemical acid-base neutralization reaction where protons are reduced on the cathode and hydroxide ions are consumed, in methanol oxidation at the cathode. So, the consumption of H2SO4 and KOH must be taken into account while comparing the different membraneless LFFC configurations. 

Acid-Base Neutralization Reactions. As defined in Chapter 4, adds and bases can either be weak or strong. In the case of the reaction between a strong acid and a strong base, an exchange reaction occurs. For example, hydrochloric acid and potassium hydroxide react in an exchange manner to form hydrogen hydroxide (WATER ) and potassium chloride. Potassium chloride is not an exception and is therefore soluble. The molecular equation can be written as... 

The principle of conductivity suppression is the reduction of background conductivity by converting the eluent to a less conductive medium (H2O) through acid-base neutralization while the analyte ions conductivity is increased, by converting them to a more conductive medium Anions are converted to their acid forms and cations to their hydroxide forms. These reactions lead to higher S/N ratios, thus significantly improving baseline stability and detection limits. 

Acid-base titration The stoichiometry of an acid-hase neutralization reaction is the same as that of any other reaction that occurs in solution. In the antacid reaction you just read about, one mole of magnesium hydroxide neutralizes two moles of hydrochloric acid. 

How does neutralization occur Recall that every water molecule contains two hydrogen atoms and one oxygen atom. As Figure 21 shows, when one hydronium ion reacts with one hydroxide ion, the product is two water molecules. This reaction occurs during acid-base neutralization. Equal numbers of hydronium ions from the acidic solution and hydroxide ions from the basic solution react to produce water. Pure water has a pH of 7, which means that it s neutral. 

When deriving net-ionic equations, be certain to start with a balanced formula equation. That way, you will end up with a balanced net-ionic equation. The formula, ionic and net-ionic equations for the reaction between hydrochloric and calcium hydroxide appear below. The net-ionic equation shows that acid-base neutralization here is the same reaction seen in the nitric add-sodium hydroxide reaction. 

The reaction of an acid and a base in aqueous solution is called a neutralization reaction. The products of a neutralization reaction are a salt and water. A salt is an ionic compound composed of a positive ion from a base and a negative ion from an acid. An example of an acid-base neutralization is the reaction of nitric acid and calcium hydroxide to form calcium nitrate and water. 

Neutralization Acidic or basic wastewaters must be neutrahzed prior to discharge. If an industry produces both acidic and basic wastes, these wastes may be mixed together at the proper rates to obtain neutral pH levels. Equahzation basins can be used as neutralization basins. When separate chemical neutralization is required, sodium hydroxide is the easiest base material to handle in a hquid form and can be used at various concentrations for in-line neutralization with a minimum of equipment. Yet, lime remains the most widely used base for acid neutr zation. Limestone is used when reaction rates are slow and considerable time is available for reaction. Siilfuric acid is the primary acid used to neutralize high-pH wastewaters unless calcium smfate might be precipitated as a resmt of the neutralization reaction. Hydrochloric acid can be used for neutrahzation of basic wastes if sulfuric acid is not acceptable. For very weak basic waste-waters carbon dioxide can be adequate for neutralization. 

A base is any material that produces hydroxide ions when it is dissolved in water. The words alkaline, basic, and caustic are often used synonymously. Common bases include sodium hydroxide (lye), potassium hydroxide (potash lye), and calcium hydroxide (slaked lime). The concepts of strong versus weak bases, and concentrated versus dilute bases are exactly analogous to those for acids. Strong bases such as sodium hydroxide dissociate completely while weak bases such as the amines dissociate only partially. As with acids, bases can be either inorganic or organic. Typical reactions of bases include neutralization of acids, reaction with metals, and reaction with salts ... 

Sn2 reactions with anionic nucleophiles fall into this class, and observations are generally in accord with the qualitative prediction. Unusual effects may be seen in solvents of low dielectric constant where ion pairing is extensive, and we have already commented on the enhanced nucleophilic reactivity of anionic nucleophiles in dipolar aprotic solvents owing to their relative desolvation in these solvents. Another important class of ion-molecule reaction is the hydroxide-catalyzed hydrolysis of neutral esters and amides. Because these reactions are carried out in hydroxy lie solvents, the general medium effect is confounded with the acid-base equilibria of the mixed solvent lyate species. (This same problem occurs with Sn2 reactions in hydroxylic solvents.) This equilibrium is established in alcohol-water mixtures ... 

As the titration begins, mostly HAc is present, plus some H and Ac in amounts that can be calculated (see the Example on page 45). Addition of a solution of NaOH allows hydroxide ions to neutralize any H present. Note that reaction (2) as written is strongly favored its apparent equilibrium constant is greater than lO As H is neutralized, more HAc dissociates to H and Ac. As further NaOH is added, the pH gradually increases as Ac accumulates at the expense of diminishing HAc and the neutralization of H. At the point where half of the HAc has been neutralized, that is, where 0.5 equivalent of OH has been added, the concentrations of HAc and Ac are equal and pH = pV, for HAc. Thus, we have an experimental method for determining the pV, values of weak electrolytes. These p V, values lie at the midpoint of their respective titration curves. After all of the acid has been neutralized (that is, when one equivalent of base has been added), the pH rises exponentially. 

A mixture of 31 5 g (0.1 mol) of 2-chloro-9-(3 -dimethylaminopropylidene)-thiaxanthene (MP 97°C) and 100 g of N-( 3-hydroxyethyl)-piperazine is heated to 130°C and boiled under reflux at this temperature for 48 hours. After cooling, the excess of N-( 3-hydroxyethyl)-piperazine Is evaporated in vacuo, and the residue is dissolved in ether. The ether phase is washed with water and extracted with dilute acetic acid, and 2-chloro-9-[3 -N-(N - -hydroxy-ethyD-piperazinylpropylidene] -thiaxanthene separated from the aqueous acetic acid solution by addition of dilute sodium hydroxide solution to basic reaction. The free base is extracted with ether, the ether phase dried over potassium carbonate, the ether evaporated and the residue dissolved in absolute ethanol. By complete neutralization of the ethanolic solution with a solution of dry hydrogen chloride in absolute ethanol, the dihydrochloride of 2-chloro-9-[3 -N-(N -(3-hydroxyethyl)-piperazinylpropylidene] -thiaxanthene is produced and crystallizes out as a white substance melting at about 250°C to 260°C with decomposition. The yield is 32 g. 

The reaction is highly exothermic due to the heat of neutralization and the heat of dilution of strong acids and a strong base (50% caustic is the currently available strength). At present there are few theoretical data on the enthalpies involved in the neutralization reaction between sulfonic acid and sodium hydroxide solution. Values of about 100 kJ/gmol have been found experimentally. The following reactions and heats are involved ... 

The reaction between an acid and a base is called a neutralization reaction, and the ionic compound produced in the reaction is called a salt. The general form of a neutralization reaction of a strong acid and a metal hydroxide that provides the hydroxide ion, a strong base, in water is... 

The net outcome of any neutralization reaction between a strong acid and a strong base in water is the formation of water from hydrogen ions and hydroxide ions. 

In Figure the hydronium ion acts as an acid because it donates a proton to a base. The hydroxide anion acts as a base because it accepts a proton from an acid. When a hydronium ion with charge +1 transfers a proton to a hydroxide ion with charge -1, the two resulting water molecules have zero charges. The pair of charges becomes a neutral pair. A proton transfer reaction such as this one, in which water is one product and a pair of charges has been neutralized, is called a neutralization reaction. 

When acids and bases come into contact with one another, a chemical reaction called a neutralization reaction takes place. A neutralization reaction is a double displacement reaction. In a double displacement reaction, the positive ions from one reactant take the place of the positive ions in the other reactant. For example, if hydrochloric acid and sodium hydroxide react with one another, the positive sodium ion in sodium hydroxide will take the place of the hydrogen ion in the hydrochloric acid ... 

Water is always one product of a neutralization reaction. The other product is a salt. In the reaction of hydrochloric acid and sodium hydroxide, the salt is sodium chloride, which is, literally, table salt. Not all acid-base reactions make sodium chloride, but they do make a salt. Salts are ionic compounds. An ionic compound is a compound that is made up of cations (positively... 

The subscript after potassium in the chemical formula for potassium sulfate shows that two potassium ions are needed. Potassium sulfate is a salt. When the two equations are put together (as they would occur when the acid and base are mixed together), they represent the double displacement neutralization reaction that occurs between sulfuric acid and potassium hydroxide ... 

Sometimes, the body needs some help regulating its acid-base balance. People who experience heartburn, for example, may resort to taking an antacid to neutralize the stomach acid creeping up their esophagus. One popular antacid, milk of magnesia, is actually magnesium hydroxide. The reaction between stomach acid and milk of magnesia is a neutralization reaction ... 

In the process of a weak acid or weak base neutralization titration, a mixture of a conjugate acid-base pair exists in the reaction flask in the time period of the experiment leading up to the inflection point. For example, during the titration of acetic acid with sodium hydroxide, a mixture of acetic acid and acetate ion exists in the reaction flask prior to the inflection point. In that portion of the titration curve, the pH of the solution does not change appreciably, even upon the addition of more sodium hydroxide. Thus this solution is a buffer solution, as we defined it at the beginning of this section. 

According to the Arrhenius definition of acids and bases, acids are substances that produce hydrogen ions (H+) in solution, and bases are substances that produce hydroxide ions (OH ) in solution. When an acid and a base combine, the hydrogen ions from the acid react with the hydroxide ions from the base to form water—a neutralization reaction. 

The neutralization equivalent is a useful means of determining the molecular weight of a carboxylic acid. The process begins with a simple neutralization reaction of acid with standard base (usually sodium hydroxide). The reaction is... 

Cesium hydroxide is the strongest base known. Its aqueous solution undergoes neutralization reactions with acids. Precipitation reactions don t yield crystaUine cesium salts because of their high solubility. 

Hydrobromic acid is a strong acid which neutralizes bases forming salts and water. The most important reactions involve the formation of bromide salts. The acid reacts with most metals, their oxides, hydroxides, carbonates... 

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