Enter your answer in the provided box. Using the K values in the table below, calculate the pH of a buffer that contains the given concentrations of a weak acid and its conjugate base. 0.50 M Na₂HPO4 and 0.90 M Na3PO4 pH Table 9.6 Common Buffers Buffer Weak Acid Conjugate Base K Acetic acid/acetate CH₂COOH CH₂COO™ 1.8 x 10-5 Bicarbonate/carbonate HCO, CO₂2- 5.6 x 10-11 Dihydrogen phosphate/ hydrogen phosphate H₂PO HPO 2- 6.2 x 10- Hydrogen phosphate/ phosphate HPO 2- PO 3 2.2 x 10-13

Enter your answer in the provided box. Using the K values in the table below, calculate the pH of a buffer that contains the given concentrations of a weak acid and its conjugate base. 0.50 M Na₂HPO4 and 0.90 M Na3PO4 pH Table 9.6 Common Buffers Buffer Weak Acid Conjugate Base K Acetic acid/acetate CH₂COOH CH₂COO™ 1.8 x 10-5 Bicarbonate/carbonate HCO, CO₂2- 5.6 x 10-11 Dihydrogen phosphate/ hydrogen phosphate H₂PO HPO 2- 6.2 x 10- Hydrogen phosphate/ phosphate HPO 2- PO 3 2.2 x 10-13

Chemistry: An Atoms First Approach

2nd Edition

ISBN:9781305079243

Author:Steven S. Zumdahl, Susan A. Zumdahl

Publisher:Steven S. Zumdahl, Susan A. Zumdahl

Chapter14: Acid- Base Equilibria

Section: Chapter Questions

Problem 4RQ: A good buffer generally contains relatively equal concentrations of weak acid and conjugate base. If...

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Fifty cm3 of 1.000 M nitrous acid is titrated with 0.850 M NaOH. What is the pH of the solution (a) before any NaOH is added? (b) at half-neutralization? (c) at the equivalence point? (d) when 0.10 mL less than the volume of NaOH to reach the equivalence point is added? (e) when 0.10 mL more than the volume of NaOH to reach the equivalence point is added? (f) Use your data to construct a plot similar to that shown in Figure 14.10 (pH versus volume NaOH added).
A good buffer generally contains relatively equal concentrations of weak acid and conjugate base. If you wanted to buffer a solution at pH = 4.00 or pH = 10.00, how would you decide which weak acidconjugate base or weak baseconjugate acid pair to use? The second characteristic of a good buffer is good buffering capacity. What is the capacity of a buffer? How do the following buffers differ in capacity? How do they differ in pH? 0.01 M acetic acid/0.01 M sodium acetate 0.1 M acetic acid/0.1 M sodium acetate 1.0 M acetic acid/1.0 M sodium acetate
Marble is almost pure CaCO3. Acid rain has a devastating effect on marble statuary left outdoors. Assume that the reaction which occurs is CoCO3(s)+ H+(aq)Ca2+(aq)+HCO3(aq) Neglecting all other competing equilibria and using Tables 15.1 and 13.2, calculate (a) K for the reaction. (b) the molar solubility of CaCO3 in pure water. (c) the molar solubility of CaCO3 in acid rainwater with a pH of 4.00.
A buffer solution with it pH of 12.00 consists of Na3PO4 and Na2HPO4. The volume of solution is 200.0 mL. (a) Which component of the buffer is present in a larger amount? (b) If the concentration of Na3PO4 is 0.400 M, what mass of Na2HPO4 is present? (c) Which component of the buffer must be added to change the pH to 12.25? What mass of that component is required?
A buffer is made by adding 0.68 g of sodium formate, NaHCOO (molar mass = 68.0 g/mol), to 1.00 L of 0.015 M formic acid, HCOOH (K a = 1.8 × 10−4). The pH of the buffer is 3.57. What will the pH be after 10.0 mL of 0.50 M HCl(aq) is added to the buffer? I know how to solve it, I just don't know what the equation of the buffer is supposed to look like. I have HCOO- <---> HCl + HCOOH, but I don't think that's right. Thank you!
You are tasked with making a buffer solution containing equal amounts of propionic acid from a 99.5 wt% solution (d = 0.993 g/mL, FW = 74.08 g/mol) and sodium propionate (solid, FW = 96.06 g/mol). What concentration of the buffer must be prepared to prevent a change in the pH by more than 0.5 pH units after the addition of 10.00 mL of 3.00 M HCl to 100.0 mL of the buffer solution? The Ka for propionic acid is 1.76 x 10-5.
What is the proper unit of molar ratio of weak acid and its conjugate base in a buffer solution? Is it mol to mol or part to part? Or is it unitless? I need to express the answer 1.45/1 = [A]/[HA] to the right unit. See image for more details. the buffer is acetic acid/sodium acetate buffer.
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