pH and pOH

Citric acid, lactic acid, malic acid, tartaric acid, phosphoric acid, acetic acid, and carbonic acid are found in many of the foods and beverages located in your refrigerator. The word acid is often thought of negatively, as if all acids are dangerous. This is actually not the case. There are so many types of acids, and their strength varies dramatically depending on how quickly they dissociate into hydrogen ions and their anion. Some acids are weak and others are strong.

Similarly, bases can be found around the house. Many household cleaning supplies are basic. Ammonia, drain cleaners, most soaps, and detergents are all bases. Like acids, the strength of these bases varies dramatically depending on how quickly they dissolve to create hydroxide ions. Some bases are weak and others are strong. Unlike the household acid examples, these household bases are not ingestible.

How can you tell if something is an acid or a base? In this topic, you will learn to calculate the pH and pOH of solutions. By doing this, you will be able to determine whether a substance is an acid or a base, as well as its relative strength.

Essential Questions

• What makes a substance an acid or a base, and how its strength measured?
• How are the different acid/base theories related?