Chemistry: Acids, Bases, and Indicators
| Grade Level: | 5, 8, and High School |
| Where Taught: | Laboratory (with working sinks and drains) |
| # Students: | Up to 30 students, plus one observer |
| Time needed for presentation: | 50-60 minutes |
| Georgia Performance Standards (GPS) | |
| Chemistry: Acids, Bases, and Indicators Enrichment Activities | |
We will need ten minutes between sessions to cleanup and prepare for the next session.
The Acids, Bases, and Indicators module is designed to educate students about chemistry and stimulate their enthusiasm for the subject. Many students view chemistry as one of the more difficult sciences, and this module is designed to convince them that chemistry is interesting, fun, and stimulating. We begin with a brief introduction to chemistry and matter. This is followed by a discussion of the fundamental properties of acids and bases. We then discuss the use off pH indicators, including litmus paper, phenolphthalein, thymol blue, and paranitrophenol as tools for determining the acid/base characteristics of compounds. The level of the discussion is tailored to the age and background of each class. Demonstrations are performed to reinforce the concepts presented, and to stimulate the students’ curiosity. The students conduct hands-on experiments designed to give them experience in scientific thinking, methodology, and laboratory safety.
Students use pipettes to add PT, TP and PP (phenolphthalein, thymolpthalein, and paranitrophenol) to a base solution to create a “rainbow”. We pre-measure the amount of indicator that elementary students use. Older students get to work out the amount that they need themselves.
