HPA Standards
To make the HPA standards, we defined the concentrations we wanted to be 2 mM, 1 mM, and 0.5 mM HPA. We then solved to discover that 30 mg of HPA in 100 mL of water would make a 2 mM solution of HPA. We then carried out a serial dilution.
To complete the serial dilution, we filled one 100 mL volumetric flask with 100 mL of water and two 100 mL volumetric flasks with 50 mL of water. Then, placed a stir bar and the 30 mg of HPA into the flask with 100 mL of water. This solution was placed on a stir plate and allowed to stir until the HPA was fully dissolved, creating the 2 mM solution. After the HPA was fully dissolved, 50 mL of the 2mM solution was poured into one of the other two flasks. This step created the 1 mM solution. This process was repeated by pouring 50 mL of the 1 mM solution into the remaining flask with 50 mL of water to create the 0.5 mM solution.
After each concentration was made, they were transferred to beakers where a pH 5 buffer tablet was placed into each standard.
