Neutralization Reaction - Acids + BasIntroduction and Definitions:

A salt is any compound which can be derived from neutralization of an acid and a base. The word "neutralization" is used because the acid and base properties of H+ and OH- are destroyed or neutraliz the reaction, H+ and OH- combine to form HOH or water molecules. A neutralization is a type of doub replacement reaction. A salt is the product of an aci reaction and is a much broader term then common salt as shown in the first reaction.

The following are some examples of neutralization reactions to form salts. a. HCl + NaOH --> NaCl + HOH b. H2SO4 + 2 NH4OH --> (NH4)2SO4 + 2 HOH c. 2 NaOH + H2CO3 --> N2CO3 + 2 NaOH

See the graphic on the left. Carbon dioxide in the b reacts first with the water to form carbonic acid: CO2 + H2O --> H2CO3

The carbonic acid then further reacts with the lime in the neutralization reaction. The phenolphthalein in the presence of base and turns colorless when all base has been neutralized and there is a slight exces the carbonic acid.

d. Lime water: Ca(OH)2 + H2CO3 --> CaCO3 + 2 H Practice: HNO3 + KOH --> H3PO4 + 3 NaOH -->

+ +

The non-metal oxide gases react with water to produce acids (ammonia produces a base). Example: SO2 + HOH === H2SO3 2 NO2 + HOH === HNO2 + HNO3 Cl2 + HOH === HClO + HCl SO3 + HOH--> NH3 + HOH -->

Health Effects of Acids and Bases:

Acids and bases are examples of corrosive poisons react locally on tissue cells. Chemicals that are very or very acidic are reactive. These chemicals can cau severe burns. Automobile battery acid is an acidic chemical that is reactive. Automobile batteries cont stronger form of some of the same acid that is in ac Household drain cleaners often contain lye, a very chemical that is reactive.

In the home the corrosive gases are produced by smoking, aerosol oven cleaners, disinfectant sprays, window cleaners, etc. The improper mixing of a toilet bowl cleaner (HCl) or any acid with a chlorine-type bleach may produce fatal results from the generation of chlorine gas. The addition of ammonia to bleach also produces a poisonous gas, chloroamine.

Acids and bases are capable of causing severe "bur similar to burns produced by heat. These materials first dehydrating cellular structures. Then proteins structures are destroyed by the action of acid or bas which catalyzes the splitting of peptide bonds. Sma smaller fragments result, leading to the ultimate disintegration of the tissue.

The eyes and lungs are particularly sensitive to corr poisons. The cornea of the eyes is damaged by acid base burns. Pulmonary edema (filling with water) o when highly concentrated corrosive pollutants (acu poisoning) reach the lungs. The lining of the nose, and lungs become irritated and water logged (by dehydration of cells). This occurs in an attempt to d the toxic agent. This waterlogged condition prevent normal exchange of oxygen and carbon dioxide. Th victim may die of immediate suffocation, a seconda attack of bacteria leading to pneumonia, or suffer permanent lung damage. Long term subchronic acid dosage effects are less well understood.

Air pollutants such as sulfur oxides, nitrogen oxide chlorine, and ammonia all have corrosive effects on respiratory tract. The solubility of the gases in wate determines their fate. The most soluble gases, such ammonia and sulfur oxides, are promptly adsorbed moist surfaces of the upper airways causing nasal a throat irritation. Less soluble gases, such as nitroge oxides and chlorine, produce their effects in the dep the lungs causing pulmonary edema, pneumonia, an emphysema (loss of elasticity and surface area).

First-Aid Treatments Use Neutralization:

The interpretation of "Danger" and First-Aid labels household cleaners provides an exercise in the use base principles. Example:

A toilet bowl cleaner - Danger: Corrosive - produce chemical burns. Contains Hydrochloric Acid. Do n in eyes, on skin. May be fatal if swallowed. Do not vapor or fumes. First-Aid: Internal - Call physician a teaspoon of magnesia, chalk, small pieces of soap egg white, or milk. External - Eyes - Wash with wa 15 minutes. Skin - Wipe acid off gently, flood with cover with moist magnesia or baking soda. The above graphic demonstrates the following reactions. The phenolphthalein is pink in the presence of a base and colorless after the citric acid neutralizes the base.

Solution: The First-Aid consists of either diluting th coating the stomach lining, or neutralizing it. Mg(OH)2 + HCl --> MgCl2 + HOH magnesia

A bottle of drain cleaner contains lye (NaOH). First-Aid The laboratory contains red bottles for acid burns w treatment is to give citrus juice (citric acid) or vinegar contain baking soda (NaHCO3). Write the neutraliz (acetic acid). Write reactions. reaction by applying the Bronsted definition. H3C6H8O6 + NaOH --> HC2H3O2 + NaOH --> HCl +

NaHCO3 -->

NaCl + H

+ +

Bronsted acids or bases, above?

H2CO3 continues decompos make bub of CO2.

Stomach Antacids:

Antacids are supposed to decrease the amount of hydrochloric acid in the stomach by reacting with e acid. They are used in the treatment of gastric hype and peptic ulcers. Some of the ingredients in antaci Magnesia (MgO), milk of magnesia (Mg(OH)2, cal carbonate (CaCO3), sodium bicarbonate (NaHCO3)

dihydroxyaluminum sodium carbonate (NaAl(OH)2 aluminum hydroxide gel (Al(OH)3). Several of thes habe top be recognized as Bronsted bases.