View current table in a new window Each amino acid utilized in this experiment has a different side chain chemistry.
The physical and chemical properties of water play a central role in biological structure and function of the organism. The hydrogen-ion concentration of biological system is usually preferred as the pH system, which determines the pH level of dilute aqueous solutions.
In this laboratory, the data collected from the experiment will be used to graph the titration curves which help to identify an unknown amino acid.
Introduction Amino acids are simple Improve your academic results! We will write a custom essayTitration: Amino acids play a key cellular role in structure and function. Proteins themselves participate in nearly every physiological event in the cell. Since all amino acids contain at least one amino and one carboxyl group, they are classified as amphoteric substances meaning that they can act as either an acid or as a base 1.
The pH dependent equilibrium reactionThe effects of pH and buffer play a significant role in the protonation and deprotonation of water.
The survival of organisms depends on the pH levels. Due to the nature of amino acids, a titration curve can be employed to identify an unknown amino acid. A titration curve is the plot of the pH versus the volume of titrant used.
In the case of amino acids, the titrant will be both an acid and a base. The pH at which the net charge of an amino acid is zero is called the isoelectric point, or the pI.
The pI could be determined by averaging the two pKa values that flank the neutral species. At the pI, the? In this experiment, the identity of an unknown amino acid was determined through acid-base titration.
The unknown amino acid could be glutamate, lysine, or histidine. The glycine was also titrated for comparison Fig. The structural formulas of four amino acids at pH of 7. Methods The experiment was accomplished according to the procedure given by Professor. Results The glycine was titrated and dada was recorded.
The total solution of NaOH added was The Unknown 2 was titrated and dada was recorded. Figures 3 and 4 represent the exploratory titration and the accurate titration curves respectively.
Also, the dots on figures 3 and 4 show the amounts of base and acid added to the unknown solution and the pH which corresponds to that amount. Discussion and ConclusionA titration of a weak acid with a strong base is an excellent way to observe the equilibrium reactions associated with a weak acid.
The analysis of the titration curves provides a means of determining the dissociation constant of the acid. Under ideal conditions the dissociation can be used to identify an unknown acid. The pKa of the acid is equal to the pH at the midpoint of the titration curve.
To identify the unknown amino acid its pKa was used as a comparison to the known value of lysine, histidine, and glutamate.
The equivalence point of titration from the titration curve of the unknown amino acid was estimated. It was found that the equivalence point of the first, second, and third pKa s are approximate at a pH of 2.
These values were been compared with lysine, histidine, and glutamate pKa s. It was determined that the pKa s of the unknown amino acid were very close to the pKa s of glutamate 2. It was assumed that the unknown amino acid was glutamate.
There was an error that can be held accountable for the deviation from the accepted values. First, the pH meter never reported a definite value; very often the meter reported a floating number. Therefore, one has no way of knowing which reported pH was more correct.
To avoid such a problem in a future, more careful handling with equipment is necessary during the titration process to minimize the occurrence of error.Opening Hours. Call Us. Email Us [email protected]. More about Determination Of An Unknown Amino Acid From Titration Essay This is a chemistry lab report on an Acid-Base Titration experiment.
Words | 11 Pages. Identification of an Unknown Organic Acid Essay.
The Essay on Titration: Identification of an Unknown Amino Acid Biochemistry proteins. Amino acids play a key cellular role in structure and function. Titration: Identification of an Unknown Amino Acid Biochemistry Essay by arakul, College, Undergraduate, B, August download word file, 3 pages download word file, 3 pages 4 votes5/5(4). Determination of An Unknown Amino Acid From Titration Abstract Experiment 11 used a titration curve to determine the identity of an unknown amino acid. The initial pH of the solution was , and the pKa’s found experimentally were , , and The accepted pKa values were found to .
A. Pages:7 Words This is just a sample. To get a unique essay. We will write a custom essay sample on Identification of an Unknown Organic Acid specifically for you for only $ $/page. Titration: . To identify the unknown amino acid its peak was used as a comparison to the known value of lysine, histamine, and glutamate.
The equivalence point of titration from the titration curve of the unknown amino acid was estimated. Titration: Identification of an Unknown Amino Acid Biochemistry Abstract Water is important substance for all living organisms. The physical and chemical properties of water play a central role in biological structure and function of the organism.
The Essay on Titration: Identification of an Unknown Amino Acid Biochemistry proteins. Amino acids play a key cellular role in structure and function.