In this activity, students investigate the nitrate content in, for example, pond or aquarium water. The nitrite formed is subsequently determined using the Griess reaction. The intensity of the color is proportional to the amount of nitrite, and thus indirectly to the original amount of nitrate. As a result, the nitrate content can be determined using a colorimeter.
Concepts learned:
- Extinction
- Spectrophotometry
- Calibration curve
- Lambert-Beer Law