1. pH Scale What is pH?

2. pH pH means “ pondus hydrogenii” or the potential for hydrogen. The pH scale ranges from 0 to 14 where 0 is the pH of very strong acids and 14 is the pH of very strong bases 7 is a neutral solution neither acidic or basic H+ = OH- ions

3. pH of Common Substances Timberlake, Chemistry 7 th Edition, page 335

4. pH Scale Acid Base 0 7 14 Zumdahl, Zumdahl, DeCoste, World of Chemistry  2002, page 515

5. The Development of the pH Scale The pH scale was developed by Dr. Sorenson in the early 1900’s. It was published in 1920. The pH scale is based on an increase or decrease by a power of ten. Root beer is 10x more acidic than pure water. Pure water has a pH of 7 and root beer pH of 6. 10 x the # of H+ ions

6. pH Scale A solution oh pH 5 has a 2 unit change with water ( from 7 to 5 ), so it is 10 x 10 or 100x as acidic as water. A substance like your retainer cleaner that has a pH of 8 is 10x more basic than water.

7. pH scale As you go from pH 7 to pH 8 there are 10 times more OH - ions Every level of the pH scale represents a ten fold (ten times) increase in the concentration of the H + or OH - ions

8. pH An acid solution, where [H + ] > [OH - ] A basic solution, where [OH - ] < [H + ]

9. Because the pH scale is a log scale based on 10, the pH changes by 1 for every power of 10 change in the [H + ].

11. Importance List some reasons pH would be important