Submitted by: Justin TLast updated: 9/29/11
What are acids and bases?

Acids and bases are two different types of chemicals. But although they are different they are somewhat related. Acids, bases, and the products of their reactions are important to many life processes and are valuable to our industry.
Acids

The word acid comes from the Latin term acidus and “sour.” There are many different types of acids. Some acids are found in food.They often have a sour taste. They are found in things like vinegar, milk, lemons, cheese, fruits and much more.
Some other types of acids are found in animals. Some are good for the animals, but others are bad. For example, some acids are in pollution in the air. The acid in the air goes up in the sky and dissolves. Then it goes into the clouds and eventually comes back down when it rains. This is called acid rain. See exhibit A. Then the water washes off into ponds, lakes, rivers, and oceans. If the acid rain reaches animals with a certain pH level (Like frogs), than it could kill them! Those acids are bad for them. But acids found in animals can also be good. In some animals, the stomach can create an acid that helps break down food that they eat.
Exhibit A

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This diagram shows how acid affect animals with a certain pH level

Some acids are very strong. Some of these acids can break metals so these types of acids should not be tasted or even touched. Sulfuric acid (a type of acid) is one example. It is used to make fertilizers, dyes, drugs, and a couple of different types of batteries.


Bases

Bases can be thought of as the chemical opposite of acids. On the other hand, bases may feel slippery in water. Some are used in foods or medicines. These often have a bad taste. Examples of bases include baking soda, pure water, or bleach. Other bases are used in manufacturing. These are too strong to be tasted or even touched.

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Acid can be very dangerous



What happens when you combine acids and bases?

Scientists use something called the pH scale to measure how acidic or basic a liquid is. Acids and bases are encountered very often in both chemistry and in everyday living. They have opposite properties and can cancel or neutralize each other. When they are combined they produce water and salts. These have salty tastes. The reactions between acids and bases can be quite powerful. One result is that they can quickly produce gases. This is why baking soda is useful for baking these days. When it is combined with an acid such as lemon juice or sour cream in a dough mixture, it releases gases.

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Common Household prodects which contain acids and bases



How to tell if a product is acidic or basic

Scientists use a pH scale to tell the pH level of something. Everything has a pH level. These pH levels are measured on a scale from 0 to 14. If the pH level is 7-14, than it has basic ions in it and is considered to be a base. If the pH level is 0-7, than it has acidic ions in it and is considered to be an acid. If it has a pH level of 7 than it has both acids and bases in it. Distilled water has a pH of 7. Each whole number pH value below 7 is ten times more acidic than the next higher value. For example, a pH of 4 is ten times more acidic than a pH of 5.


Glossary:


Acidus: A Latin term for the word Acid
pH Level: level of acids and bases in a certain area
pH Scale: A scale used to measure the PH level of something












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Encyclopædia Britannica, Inc., 2011. Web. 12 Sept. 2011.

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Encyclopædia Britannica, Inc., 2011. Web. 22 Sept. 2011.

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