Phosphate Buffer Lab

The experiment began by adding 50 mL of phosphate buffer solution (pH 6.77) in a 150 mL beaker. Once the appropriate amount of phosphate buffer was measured, exactly 20 drops of 0.04% bromothymol blue was placed in the buffer solution. A serological pipet was then used to fill three 50 mL beakers with 5 mL of solution. Approximately 1 mL of HCl, NaOH, and H2O were distributed into each of the three beakers. The yellow solution was labeled HCl, the green solution was labeled H2O and the blue solution was labeled NaOH. To measure the absorbance level, a spectrometer had to be setup and calibrated. While the spectrometer was being prepared, the solutions were placed into three separate cuvettes. Each cuvette was then whipped clean to allow an