acid-base reaction | Definition, Examples, Formulas, & Facts | mob-con.info
So, in general, Bases are Oxides and Alkalis are Hydroxides. Alkaline are those which can Related Questions (More Answers Below). What is the difference. In modern chemistry, we have a sound understanding of acids and bases (also called alkalis). Acids and bases pervade our lives, from the laboratory to the. Strong acids conduct better due to the higher concentration of ions due to acid or alkali will have a higher rate of reaction compared with a weak acid or alkali.
The pH of a virtually pure acid, such as the sulfuric acid in car batteries, is 0, and this represents 1 mole mol of hydronium per liter l of solution.
It is interesting to observe that most of the fluids in the human body have pH values in the neutral range blood venous, 7. The most precise pH measurements are made with electronic pH meters, which can provide figures accurate to 0. However, simpler materials are also used. Best known among these is litmus paper made from an extract of two lichen specieswhich turns blue in the presence of bases and red in the presence of acids.
The term "litmus test" has become part of everyday language, referring to a make-or-break issue—for example, "views on abortion rights became a litmus test for Supreme Court nominees. For instance, paper coated with phenolphthalein changes from colorless to pink in a pH range from 8. Extracts from various fruits and vegetables, including red cabbages, red onions, and others, are also applied as indicators. Selected substances listed above are discussed briefly below. As its name suggests, citric acid is found in citrus fruits —particularly lemons, limes, and grapefruits.
Acid–base reaction - Wikipedia
It is also used as a flavoring agent, preservative, and cleaning agent. Produced commercially from the fermentation of sugar by several species of mold, citric acid creates a taste that is both tart and sweet.
The tartness, of course, is a function of its acidity, or a manifestation of the fact that it produces hydrogen ions. The sweetness is a more complex biochemical issue relating to the ways that citric acid molecules fit into the tongue's "sweet" receptors.
Citric acid plays a role in one famous stomach remedy, or antacid. This in itself is interesting, since antacids are more generally associated with alkaline substances, used for their ability to neutralize stomach acid.
- ACIDS AND BASES
- Acids and Bases
- Acid–base reaction
The fizz in Alka-Seltzer, however, comes from the reaction of citric acids which also provide a more pleasant taste with sodium bicarbonate or baking soda, a base. This reaction produces carbon dioxide gas. As a preservative, citric acid prevents metal ions from reacting with, and thus hastening the degradation of, fats in foods.
It is also used in the production of hair rinses and low-pH shampoos and toothpastes. The carboxylic acid family of hydrocarbon derivatives includes a wide array of substances—not only citric acids, but amino acids. Amino acids combine to make up proteins, one of the principal components in human muscles, skin, and hair. Carboxylic acids are also applied industrially, particularly in the use of fatty acids for making soaps, detergents, and shampoos.
There are plenty of acids found in the human body, including hydrochloric acid or stomach acid—which, in large quantities, causes indigestion, and the need for neutralization with a base.
Nature also produces acids that are toxic to humans, such as sulfuric acid. Though direct exposure to sulfuric acid is extremely dangerous, the substance has numerous applications. Not only is it used in car batteries, but sulfuric acid is also a significant component in the production of fertilizers. On the other hand, sulfuric acid is damaging to the environment when it appears in the form of acid rain. Among the impurities in coal is sulfur, and this results in the production of sulfur dioxide and sulfur trioxide when the coal is burned.
Sulfur trioxide reacts with water in the air, creating sulfuric acid and thus acid rainwhich can endanger plant and animal life, as well as corrode metals and building materials. Bases The alkali metal and alkaline earth metal families of elements are, as their name suggests, bases. A number of substances created by the reaction of these metals with nonmetallic elements are taken internally for the purpose of settling gastric trouble or clearing intestinal blockage.
For instance, there is magnesium sulfate, better known as Epsom saltswhich provide a powerful laxative also used for ridding the body of poisons.
Aluminum hydroxide is an interesting base, because it has a wide number of applications, including its use in antacids. Aluminum hydroxide is also used in water purification, in dyeing garments, and in the production of certain kinds of glass.
A close relative, aluminum hydroxychloride or Al2 OH 5Cl, appears in many commercial antiperspirants, and helps to close pores, thus stopping the flow of perspiration.
Baking soda, known by chemists both as sodium bicarbonate and sodium hydrogen carbonate, is another example of a base with multiple purposes. Baking soda is also used in fighting fires, because at high temperatures it turns into carbon dioxidewhich smothers flames by obstructing the flow of oxygen to the fire. Of course, baking soda is also used in baking, when it is combined with a weak acid to make baking powder.
The reaction of the acid and the baking soda produces carbon dioxide, which causes dough and batters to rise. In a refrigerator or cabinet, baking soda can absorb unpleasant odors, and additionally, it can be applied as a cleaning product. Another base used for cleaning is sodium hydroxide, known commonly as lye or caustic soda. Unlike baking soda, however, it is not to be taken internally, because it is highly damaging to human tissue—particularly the eyes. In the process of doing so, however, relatively large amounts of lye may generate enough heat to boil the water in a drain, causing the water to shoot upward.
For this reason, it is not advisable to stand near a drain being treated with lye. In a closed oven, this is not a danger, of course; and after the cleaning process is complete, the converted fats now in the form of soap can be dissolved and wiped off with a sponge. Wentworth; and James P. What Makes a Lemon Sour? Rourke Book Company, Illustrated by Denis Bishopand Jim Robins.
Introductory Chemistry A Foundation, 4th ed. A substance that, in its edible form, is sour to the taste, and in non-edible forms, is often capable of dissolving metals. Acids and bases react to form salts and water. A term referring to the soluble hydroxides of the alkali and alkaline earth metals. Once "alkali" was used for the class of substances that react with acids to form salts; today, however, the more general term base is preferred.
An adjectival term used to identify the degree to which a substance displays the properties of a base. The negatively charged ion that results when an atom gains one or more electrons. A substance in which water constitutes the solvent. A large number of chemical reactions take place in an aqueous solution.
The first of three structural definitions of acids and bases.
Properties of Strong and Weak Acids
Formulated by Swedish chemist Svante Arrheniusthe Arrhenius theory defines acids and bases according to the ions they produce in an aqueous solution: A substance that, in its edible form, is bitter to the taste. Bases tend to be slippery to the touch, and in reaction with acids they produce salts and water.
The second of three structural definitions of acids and bases. The positively charged ion that results when an atom loses one or more electrons. A generic term used for any substance studied in chemistry—whether it be an element, compound, mixture, atom, molecule, ion, and so forth. The acid and base produced when an acid donates a single proton to a base.Acids, Bases and Alkalis - AQA Chemistry
In the reaction that produces this pair, the acid and base switch identities. By donating aproton, the acid becomes a conjugate base, and by receiving the proton, the base becomes a conjugate acid.
A base formed when an acid releases a proton. An atom or atoms that has lost or gained one or more electrons, and thus has a net electric charge. There are two types of ions: A form of chemical bonding that results from attractions between ions with opposite electric charges. A compound in which ions are present.
Ionic compounds contain at least one metal and non metal joined by an ionic bond. The third of three structural definitions of acids and bases. Formulated by American chemist Gilbert N. LewisLewis theory defines an acid as the reactant that accepts an electron pair from another reactant in a chemical reaction, and a base as the reactant that donates an electron pair to another reactant. A logarithmic scale for determining the acidity or alkalinity of a substance, from 0 virtually pure acid to 7 neutral to 14 virtually pure base.
A term describing scientific definitions based purely on experimental phenomena. The acidity of the body fluids is maintained within narrow limits.
This acidity is expressed in terms of the pH of a solution, values exceeding 7 representing alkalinity and less than 7 acidity. The pH of a solution is an expression of the… The idea that some substances are acids whereas others are bases is almost as old as chemistryand the terms acid, base, and salt occur very early in the writings of the medieval alchemists.
Acids were probably the first of these to be recognized, apparently because of their sour taste. Other properties associated at an early date with acids were their solvent, or corrosive, action; their effect on vegetable dyes; and the effervescence resulting when they were applied to chalk production of bubbles of carbon dioxide gas.
Bases or alkalies were characterized mainly by their ability to neutralize acids and form salts, the latter being typified rather loosely as crystalline substances soluble in water and having a saline taste. In spite of their imprecise nature, these ideas served to correlate a considerable range of qualitative observations, and many of the commonest chemical materials that early chemists encountered could be classified as acids hydrochloric, sulfuric, nitric, and carbonic acidsbases soda, potash, lime, ammoniaor salts common saltsal ammoniacsaltpetre, alum, borax.
The absence of any apparent physical basis for the phenomena concerned made it difficult to make quantitative progress in understanding acid—base behaviour, but the ability of a fixed quantity of acid to neutralize a fixed quantity of base was one of the earliest examples of chemical equivalence: In addition, it was found quite early that one acid could be displaced from a salt with another acid, and this made it possible to arrange acids in an approximate order of strength.
It also soon became clear that many of these displacements could take place in either direction according to experimental conditions. This phenomenon suggested that acid—base reactions are reversible —that is, that the products of the reaction can interact to regenerate the starting material. It also introduced the concept of equilibrium to acid—base chemistry: Apart from their theoretical interest, acids and bases play a large part in industrial chemistry and in everyday life.
Sulfuric acid and sodium hydroxide are among the products manufactured in largest amounts by the chemical industryand a large percentage of chemical processes involve acids or bases as reactants or as catalysts. Almost every biological chemical process is closely bound up with acid—base equilibria in the cell, or in the organism as a whole, and the acidity or alkalinity of the soil and water are of great importance for the plants or animals living in them.
Both the ideas and the terminology of acid—base chemistry have permeated daily life, and the term salt is especially common. Theoretical definitions of acids and bases Hydrogen and hydroxide ions The first attempt at a theoretical interpretation of acid behaviour was made by Antoine-Laurent Lavoisier at the end of the 18th century. Lavoisier supposed that all acids must contain oxygenand this idea was incorporated in the names used for this element in the various languages; the English oxygen, from the Greek oxys sour and genna production ; the German Sauerstoff, literally acid material; and the Russian kislorod, from kislota acid.
Following the discovery that hydrochloric acid contained no oxygen, Sir Humphry Davy about first recognized that the key element in acids was hydrogen.