User:Ashish Bhattarai/Notebook/EBC 571/2017/09/06

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The first process for today's lab involved Titrant standardization where we used Potassium Hydrogen Phthalate to standardize NaOH. Phenolphthalein was used as an indicator. The main goal of this standardization process is to have a feel of how much of NaOH might be needed for the important part of this lab experiment (Amino acid titration). The standardization process shows that about 27.35 mL of NaOH was needed. The number is indicated in the table below. Due to the lack of time, we were not able to perform titration for all three of our amino acids. The titration was performed for Phenylalanine and Isoleucine. 10 ml of 250 uM amino acid solution is transferred to a beaker. 10 ml of 200 uM HCl and 10 mL of water is added to the beaker. pH probe is used to calculate the initial pH. Titrant (NaOH) was added in 2-4 mL intervals and the beaker was swirled for good mixing. The titrant was added until the pH reached 10 or 11. Due to the time limit we performed titration such that the pH reached about 10 for both of the amino acids. The table below shows the amount of NaOH that was added to get to the pH range of 10 for both amino acids.