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Tris(hydroxymethyl)aminomethane, commonly called TRIS or Trizma, is often used as a buffer in biochemical studies. Its buffering range is pH 7 to 9, and Kb is 1.19 × 10−6 for the aqueous reaction
a. What is the optimal pH for TRIS buffers?
b. Calculate the ratio [TRIS]/[TRISH+] at pH = 7.00 and at pH = 9.00.
c. A buffer is prepared by diluting 50.0 g TRIS base and 65.0 g TRIS hydrochloride (written as TRISHCl) to a total volume of 2.0 L. What is the pH of this buffer?
What is the pH after 0.50 mL of 12 M HCl is added to a 200.0-mL portion of the buffer?
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