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ACIDS & BASES

ACIDS & BASES. ACIDS & BASES. ACIDS AND BASES ARE EVERYWHERE Every liquid you see will probably have either acidic or basic traits Acids are compounds that break up into hydrogen (H+) ions and another compound when placed in an aqueous solution.

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ACIDS & BASES

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  1. ACIDS & BASES

  2. ACIDS & BASES ACIDS AND BASES ARE EVERYWHERE • Every liquid you see will probably have either acidic or basic traits • Acids are compounds that break up into hydrogen (H+) ions and another compound when placed in an aqueous solution. • Bases are compounds that break up into hydroxide (OH-) ions and another compound when placed in an aqueous solution. http://www.chem4kids.com/files/react_acidbase.html

  3. Let's change the wording a bit. If you have an ionic compound and you put it in water, it will break apart into two ions. If one of those ions is H+, the solution is acidic. If one of the ions is OH-, the solution is basic. There are other ions that make acidic and basic solutions, but we won't be talking about them here. ACIDS & BASES Let's change the wording a bit. If you have an ionic compound (two or more ions* held next to each other by electrical attraction) and you put it in water, it will break apart into two ions. If one of those ions is H+, the solution is acidic. If one of the ions is OH-, the solution is basic. *ion = atom or molecule where the total number of electrons is not equal to the total number of protons, giving it a net positive or negative electrical charge

  4. ACIDS & BASES Here are a couple of definitions you should know: Acid: A solution that has an excess of H+ ions. It comes from the Latin word acidus that means "sharp" or "sour". Base: A solution that has an excess of OH- ions. Another word for base is alkali.Aqueous: A solution that is mainly water. Think about the word aquarium. AQUA means water. Strong Acid: An acid that has a very low pH (0-4).Strong Base: A base that has a very high pH (10-14). Weak Acid: An acid that only partially ionizes in an aqueous solution. That means not every molecule breaks apart. They usually have a pH close to 7 (3-6). Weak Base: A base that only partially ionizes in an aqueous solution. That means not every molecule breaks apart. They usually have a pH close to 7 (8-10). Neutral: A solution that has a pH of 7. It is neither acidic nor basic.

  5. ACIDS & BASES Let’s let Tim and Moby explain: ACIDS & BASES

  6. pH SCALE That pH scale we talked about is actually a measure of the number of H+ ions in a solution. If there are a lot of H+ ions, the pH is very low. If there are a lot of OH- ions, that means the number of H+ ions is very low, so the pH is high.

  7. pH SCALE www.kmle.co.kr Strong Acid: An acid that has a very low pH (0-4).Strong Base: A base that has a very high pH (10-14). Neutral: A solution that has a pH of 7. It is neither acidic nor basic.

  8. pH SCALE

  9. pH SCALE How pH is Measured There are many high-tech devices that are used to measure pH in laboratories. One easy way that you can measure pH is with a strip of litmus paper. When you touch a strip of litmus paper to something, the paper changes color depending on whether the substance is acidic or basic. If the paper turns red, the substance is acidic, and if it turns blue, the substance is basic.

  10. The Red Cabbage Test As we have seen, acids and bases have the property of modifying the color of certain substances. This is the case with the juice of the red cabbage. This liquid has a blue-violet color, but when it comes in contact with acidic substances it becomes red, while in contact with basic substances it becomes green and even yellow. Let's see how it is possible to use the juice of the red cabbage to measure the pH of various substances. Pour some drops of this liquid on a white surface and observe its changes of color when it is mixed with vinegar or with baking soda. You will see that this liquid becomes red in contact with vinegar or lemon juice, while it becomes green in contact with baking soda. http://www.funsci.com/fun3_en/acids/acids.htm#6

  11. pH SCALE Dear Tim and Moby, How can I find the “pH” of water?

  12. Acid rain Visit the following link sponsored by the EPA (Environmental Protection Agency) to learn about ACID RAIN and how it affects the environment and the living organisms in the environment.

  13. Tie Dye and the Science of Color Acids & Bases: Additional Resources and Games

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