Colorimeters are analytical devices commonly used in science labs to measure the concentration of a solution from its light absorbing properties. Colorimeters are extremely useful and flexible lab instruments for a wide range of science education labs. Some examples of how they are used include:
- Color and absorbance – Investigate the relationship between the color of a substance and absorption of light at different wavelengths. See Lab 1: Introduction to Colorimetry
- Beer’s Law – Investigate the relationship between concentration and absorbance using colored solutions (eg. food dye, copper sulfate). Calculate molar extinction coefficient. See Lab 2: Beer’s Law and Molar Extinction Coefficients
- Nitrogen cycle – Quantify the breakdown (oxidation) of ammonia into nitrite and nitrate by nitrification bacteria. See Lab 3: Ammonia and nitrate measurements
- Water quality – Measure several water parameters such as turbidity, chlorine content, pH, water hardness, phosphate content and more;
- Population growth – Measure the turbidity of a microbial culture over time, which serves as an indicator of population growth;
- Enzyme kinetics – Measure the activity of an enzyme over time, even under different environmental conditions (temperature, pH, inhibitors, substrate);
via Open source DIY kit — Colorimeter User Manual.
