Since phosphoric acid is polyprotic, it can create several buffer regions. One buffer forms between H2PO4- and HPO42-. Given the conditions below, what is the pH of this buffer solution? = 6.23 x 10-8 Канарот 0.50 M H2PO4- + 0.50 M HPO42- pH of buffer=[?] pH of Buffer I pH of Buffer Enter

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
Chapter1: Chemical Foundations
Section: Chapter Questions
Problem 1RQ: Define and explain the differences between the following terms. a. law and theory b. theory and...
icon
Related questions
Question
### Phosphoric Acid Buffer Regions

Phosphoric acid is a polyprotic acid, meaning it can dissociate multiple times, creating several buffer regions. One significant buffer system involves the equilibrium between the dihydrogen phosphate ion (H₂PO₄⁻) and the hydrogen phosphate ion (HPO₄²⁻). This buffer system can be used to maintain pH in specific ranges.

#### Buffer System Between H₂PO₄⁻ and HPO₄²⁻

Given the dissociation constant (Ka) and the concentrations of the acid and its conjugate base, we can calculate the pH of the buffer solution. For the given buffer system:

- Ka(H₂PO₄⁻) = 6.23 × 10⁻⁸
- Concentrations: 
  - 0.50 M H₂PO₄⁻
  - 0.50 M HPO₄²⁻

#### pH Calculation

To find the pH of this buffer solution, we use the Henderson-Hasselbalch equation:

\[ \text{pH} = \text{pKa} + \log \left( \frac{[\text{Base}]}{[\text{Acid}]} \right) \]

Given that the concentrations of the acid and base are equal:

\[ \text{pH} = \text{pKa} \]

To find pKa, we take the negative logarithm of Ka:

\[ \text{pKa} = -\log(6.23 \times 10⁻⁸) \]

Therefore, the pH of the buffer is simply the pKa value. Use the equation above for the calculation.

---

#### Interactive Element

At the bottom of the image, there is an interactive element for users to input the calculated pH value. Users can type in their answer in the provided text box and then click the "Enter" button to submit their response, likely to check if it is correct.
Transcribed Image Text:### Phosphoric Acid Buffer Regions Phosphoric acid is a polyprotic acid, meaning it can dissociate multiple times, creating several buffer regions. One significant buffer system involves the equilibrium between the dihydrogen phosphate ion (H₂PO₄⁻) and the hydrogen phosphate ion (HPO₄²⁻). This buffer system can be used to maintain pH in specific ranges. #### Buffer System Between H₂PO₄⁻ and HPO₄²⁻ Given the dissociation constant (Ka) and the concentrations of the acid and its conjugate base, we can calculate the pH of the buffer solution. For the given buffer system: - Ka(H₂PO₄⁻) = 6.23 × 10⁻⁸ - Concentrations: - 0.50 M H₂PO₄⁻ - 0.50 M HPO₄²⁻ #### pH Calculation To find the pH of this buffer solution, we use the Henderson-Hasselbalch equation: \[ \text{pH} = \text{pKa} + \log \left( \frac{[\text{Base}]}{[\text{Acid}]} \right) \] Given that the concentrations of the acid and base are equal: \[ \text{pH} = \text{pKa} \] To find pKa, we take the negative logarithm of Ka: \[ \text{pKa} = -\log(6.23 \times 10⁻⁸) \] Therefore, the pH of the buffer is simply the pKa value. Use the equation above for the calculation. --- #### Interactive Element At the bottom of the image, there is an interactive element for users to input the calculated pH value. Users can type in their answer in the provided text box and then click the "Enter" button to submit their response, likely to check if it is correct.
Expert Solution
trending now

Trending now

This is a popular solution!

steps

Step by step

Solved in 2 steps with 2 images

Blurred answer
Knowledge Booster
Solutions
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, chemistry and related others by exploring similar questions and additional content below.
Similar questions
  • SEE MORE QUESTIONS
Recommended textbooks for you
Chemistry
Chemistry
Chemistry
ISBN:
9781305957404
Author:
Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste
Publisher:
Cengage Learning
Chemistry
Chemistry
Chemistry
ISBN:
9781259911156
Author:
Raymond Chang Dr., Jason Overby Professor
Publisher:
McGraw-Hill Education
Principles of Instrumental Analysis
Principles of Instrumental Analysis
Chemistry
ISBN:
9781305577213
Author:
Douglas A. Skoog, F. James Holler, Stanley R. Crouch
Publisher:
Cengage Learning
Organic Chemistry
Organic Chemistry
Chemistry
ISBN:
9780078021558
Author:
Janice Gorzynski Smith Dr.
Publisher:
McGraw-Hill Education
Chemistry: Principles and Reactions
Chemistry: Principles and Reactions
Chemistry
ISBN:
9781305079373
Author:
William L. Masterton, Cecile N. Hurley
Publisher:
Cengage Learning
Elementary Principles of Chemical Processes, Bind…
Elementary Principles of Chemical Processes, Bind…
Chemistry
ISBN:
9781118431221
Author:
Richard M. Felder, Ronald W. Rousseau, Lisa G. Bullard
Publisher:
WILEY