1. Assignment # Acidic, Basic, and Neutral Solutions Biology Mrs. McCarthy Wednesday, November 18, 2015

2. I. Acidic, Basic, and Neutral Solutions Acidic, Basic, and Neutral Solutions A.Solutions are acidic, basic, or neutral depending on the concentration of hydrogen ions (H+) in the solution.

3. 1.Acidic solutions contain more hydrogen ions (H+) Release hydrogen as they dissolve HCl H+ Cl-

4. Examples: grapefruit juice, vinegar, coffee, digestive juices

5. 2.Basic solutions contain more hydroxide ions (OH-) Release hydroxide ions as they dissolve NaOH Na+ OH-

6. Examples: baking soda, soap, egg whites, bleach

7. 2.Neutral solutions Have an equal amount of hydrogen and hydroxide ions H2OH2O H+ OH-

8. Examples: pure, distilled water

9. I. Acidic, Basic, and Neutral Solutions Acidic, Basic, and Neutral Solutions B.pH scale p = potential H = hydrogen ions Standard scale of hydrogen ions present in a solution There is a 10x difference between each number in the pH scale

11. Example pH 2 is 10x stronger than pH 3 pH 3 is 10x stronger than pH 4 Therefore: pH 2 is 100x stronger than pH 4

12. How many times more acidic is pH 5 than pH 8? How many times more basic is pH 11 than pH 7? 1,000 times 10,000 times

13. Scientific notation Scientific notation can be used to show the difference between numbers on the pH scale. Scientific notation is a way to make these numbers easier to work with. In scientific notation, you move the decimal place until you have a number between 1 and 10. Then you add a power of ten that tells how many places you moved the decimal. Here are some examples of scientific notation and the numbers it represents: AbbreviationNumber 1.0 x 10 -5.00001 2.5 x 10 -3.0025 1.0 x 10 2 100 3.4 x 10 2 340 1.0 x 10 5 100,000 10 5 100,000 6.0 x 10 6 6,000,000

14. Use scientific notation to show how many times more acidic pH 2 is than pH 12:scientific notation 2 is 10 places away from 12 on the scale 10 10 = 10000000000 OR 1 x 10 10 times more acidic

15. Practice: 1.Write 123,000,000,000 in scientific notation. 2.Write 0.00000034 in scientific notation.