BCH4160/2011:Notebook/Laura Lee/2011/09/06

Methyl Red

This experiment was done in order to determine the acid dissociation constant of methyl red indicator.

Materials

• Methyl Red indicator
• Buffers at various pH levels
• pH meter
• UV spectrophotometer

Procedure

1. Use premade buffers of various levels (pH 3.82, 4.35, 4.91, 6.05, 6.76, 7.12, and 7.36).
2. Add 150μL of methyl red to a cuvette. Add 1mL of a particular buffer to that cuvette.
3. Measure the absorbance over a wide wavelength range using a spectrophotomer.
4. Repeat for each buffer.
5. Graph absorbance versus wavelength for each buffer.

Data/Results

Raw Data: File:Buffers raw data.xls

• Note: Graph below is not normalized.

Contact

This experiment was done with High Point University student Jigesh Patel.