Answer the following questions: In a laboratory scale, a biochemist was asked to study the structure of the mRNA component of the Moderna vaccine. To do so, they need to first prepare 500.0 mL of 1.00 M of the Tris buffer solution of pH 7.45. The available reagents in the lab are the following: pka = 8.07 Tris base Tris-HCI MW=121.14 g/mol MW=157.56 g/mol a. Calculate the amounts of tris base and tris-HCI needed to prepare the buffer solution, in moles and grams. After this calculation, it was found that the reagents available were only Tris-base and 1.250M HCI. b. Using these new set of reagents, what amounts (in mL and g) of each are needed for the buffer? Note: You can imagine this similarly to NH3 and NH4Cl After the buffer preparation, 2.000 mL of 1.250 M HCI was accidentally added into the buffer solution c. Calculate the new pH of the solution. To correct the pH of the tris buffer solution and revert it back to pH = 7.45, a certain volume of 1.000 M NaOH must be added. d. Calculate the volume (in mL) of 1.000 M NaOH needed to bring the pH of the buffer solution back to the desired pH.

Answer the following questions: In a laboratory scale, a biochemist was asked to study the structure of the mRNA component of the Moderna vaccine. To do so, they need to first prepare 500.0 mL of 1.00 M of the Tris buffer solution of pH 7.45. The available reagents in the lab are the following: pka = 8.07 Tris base Tris-HCI MW=121.14 g/mol MW=157.56 g/mol a. Calculate the amounts of tris base and tris-HCI needed to prepare the buffer solution, in moles and grams. After this calculation, it was found that the reagents available were only Tris-base and 1.250M HCI. b. Using these new set of reagents, what amounts (in mL and g) of each are needed for the buffer? Note: You can imagine this similarly to NH3 and NH4Cl After the buffer preparation, 2.000 mL of 1.250 M HCI was accidentally added into the buffer solution c. Calculate the new pH of the solution. To correct the pH of the tris buffer solution and revert it back to pH = 7.45, a certain volume of 1.000 M NaOH must be added. d. Calculate the volume (in mL) of 1.000 M NaOH needed to bring the pH of the buffer solution back to the desired pH.

Chemistry

10th Edition

ISBN:9781305957404

Author:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Publisher:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Chapter15: Acid-base Equilibria

Section: Chapter Questions

Problem 91AE: Tris(hydroxymethyl)aminomethane, commonly called TRIS or Trizma, is often used as a buffer in...

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