With the acid, HCl, the pH of the tap water went from 7 to 1.5 after 30 drops, indicating that the concentration of hydrogen ions increased significantly. With the base, NaOH, the pH of the tap water changed from 7 to 12 after 30 drops, indicating that the concentration of of hydrogen ions decreased significantly. These changes occurred in the tap water because there are no chemical buffers present in water. In the potato homogenate, when 30 drops of HCl were added the pH changed from 6 to 3.5 (a less significant increase in the concentration of hydrogen ions), and when 30 drops of NaOH were added the pH changed from 6 to 10 (a less significant decrease in the concentration of hydrogen ions). The changes in the pH levels of the potato were
