pH I. pH—Stands for the power (or potential) of hydrogen A. pH measures the amount of hydrogen ions (H+) in a solution. B. pH indicates whether a substance is an acid or base.

II. Acid—A compound that produces hydrogen ions (H+) or hydronium ions (H3O+)in solution A. pH of an acid = less than 7 B. The more hydrogen ions an acid has, the stronger the acid is.

III. Base—A compound that produces hydroxide ions (OH-) A III. Base—A compound that produces hydroxide ions (OH-) A. pH of a base = greater than 7 B. The more hydroxide ions a base has, the stronger the base is.

IV. Neutral—Not an acid or a base A. neutral = 7 B IV. Neutral—Not an acid or a base A. neutral = 7 B. The farther an acid or base’s pH is from 7, the stronger the acid or base.

V. pH indicators— A. Change color in an acid or base B V. pH indicators— A. Change color in an acid or base B. Examples are litmus paper, cabbage juice, pH paper. C. Universal indicator—shows a different color for each pH; pH paper is this type.

VI. Safety Precautions for Strong Acids and Bases A. Never touch or taste. B. Wear eye protection. C. Handle with care. pH Scale: 0 7 14 acids neutral base

VII. Buffers—substances that have the ability to neutralize acids Ex: blood For extra info on Buffers see link below: http://www.chemistry.wustl.edu/~edudev/LabTutorials/Buffer/Buffer.html Acid-base buffers confer resistance to a change in the pH of a solution when hydrogen ions (protons) or hydroxide ions are added or removed. An acid-base buffer typically consists of a weak acid, and its conjugate base (salt). Buffers work because the concentrations of the weak acid and its salt are large compared to the amount of protons or hydroxide ions added or removed. When protons are added to the solution from an external source, some of the base component of the buffer is converted to the weak-acid component (thus using up most of the protons added); when hydroxide ions are added to the solution (or, equivalently, protons are removed from the solution), protons are dissociated from some of the weak-acid molecules of the buffer, converting them to the base of the buffer (and thus replenishing most of the protons removed).