Abstract Experiment 11 used a titration curve to determine the identity of an unknown amino acid. The initial pH of the solution was 1.96, and the pKa's found experimentally were 2.0, 4.0, and 9.85. The accepted pKa values were found to be 2.10, 4.07, and 9.47. The molecular weight was calculated to be 176.3 while the accepted value was found to be 183.5. The identity of the unknown amino acid was established to be glutamic acid, hydrochloride. Introduction                                     Amino acids are simple monomers which are …showed first 75 words of 1634 total…

…showed last 75 words of 1634 total…equivalence points and the D volume (used in calculating the molecular weight). The half-equivalence points were directly used to find the pKa values of the unknown. The molecular weight could also be calculated. This data led to the determination of the identity of the unknown amino acid--glutamic acid, hydrochloride. References Jicha, D.; Hasset, K. Experiments in General Chemistry; Hunt: Dubuque, 1991:37-53. Kotz, J.C.: Treichel , P. Jr. Chemistry and Chemical Reactivity; Harcourt-Brace: Fort Worth, 1996; 816-         837.