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Table of Contents
1. Properties of Acids
2. Properties of Bases
3. pH scale



Properties of Acids:

Acids are compounds whose characteristic properties include the kinds of reactions they undergo. “An acid is a substance that tastes sour, reacts with metals and carbonates, and turns blue litmus paper red.” (Frank,Little, Miller). Some acids that you commonly see are hydrochloric acids, nitric acid, sulfuric acids, carbonic acids, and acetic acids. These acids are seen in many sour tasting foods such as lemons, grapefruits, apples, etc. Even though many acids are sour, you shouldn’t taste it to test if the compound is an acid or not. For example: scientists never taste the chemical, they use scientific tools to test if the compound is sour or not.


Acids produce hydrogen gas when they react with metals. Some metals do not react this way. Some that do are magnesium, zinc, and iron. When they react metals disappear in the solution. This is why acids are called corrosive. This means that they eat away at the other materials. Acids also react with carbonate ions. Carbonate contains carbon and oxygen atoms bonded together which causes a negative charge. Carbon dioxide is a product of an acids reaction with carbonates.


Litmus paper is an easy way to identify quickly wither an unknown compound is and acid or a base. Litmus is an example of an indicator, which is a compound that changes different colors when it touches an acid or base. Vinegar, lemon juice, and other “sour” acids can turn the litmus paper from blue to red. (Frank, Little, Miller).



Properties of Bases:

Another group of compounds that can be identified by their common properties is bases. “A base is a substance that tastes bitter, feels slippery, and turns red litmus paper blue.” (Frank,Little, Miller) Bases are the direct opposite of acids. A common base would contain sodium hydroxide, calcium hydroxide, and ammonia.


Bases are extremely bitter, and don’t taste good at all. This bitter taste is caused by base quinine. Soaps, shampoos, detergents (or anything in general that contains soap) is an example of something that tastes bitter. So, you wouldn’t want to taste soap! (Newmark).


Whenever you wash your hands, don’t you feel that slippery gush? The slippery feeling from the soap is another characteristic that bases have. But not all bases have that slippery nice feeling. A lot of strong bases can irritate your skin or practically burn it. So, scientists don’t use this characteristic either to test if something is a base. (Frank, Little, and Miller).


Litmus paper also tests on bases too. Bases turn red litmus paper into blue. Bases react with indicators just like acids. This test is reliable and safe. Scientists use the letter B to indicate which color litmus turns for acids or bases. (Newmark).

Bases that dissolve in water are called alkalids. When the alkalids dissolve they create hydroxide ions. Acids, when dissolved in water, create hydrogen ions. When acids and bases react together, in water, the hydrogen and hydroxide ions neutralize each other. (Newmark).



pH scale-

A pH scale is a range of numbers (pH numbers also) chemists use to describe if something is acid or alkaline. Acids range from 1 to 6; Alkalis range from 8 to 14. The number 7 represents that the acid/alkaline is neutral. For example, if you mix together the quantities of an acid and alkaline, they neutralize and produce a neutral salt. Neutral salts don’t burn like acids and alkalis do. This pH scale is the same thing as litmus paper test. Also, the pH scale is an example of an indicator. (Chisholm, Jane, and Mary Johnson)





Acids and Bases!


























Citations-
Book Sources-
-Newmark, Ann. Chemistry. New York: Dorling Kindevsley, 1993. 232.
-Frank, David, John Little, and Steve Miller. Chemical Interactions. Pearson Prentice Hall, 2009. 98-102.
-Chisholm, Jane, and Mary Johnson. Introduction to chemistry. London: Publishing Ltd, 1983. 28-29.
Xtramormal- "Acids and Bases." Xtranormal. Web. 16 May 2011.

Pictures-
-Food pH Scale." livingpaleo.com. Web. 17 May 2011. <http://www.livingpaleo.com/articles/images/food_ph_scale.jpg>.
-Acids & Bases." saskschools.ca. Web. 18 May 2011.
Video-
-"Acids and Bases." Youtube.com. Web. 17 May 2011. <http://www.youtube.com/watch?v=lt516msklcI>.