One of the buffer systems used to control the pH of blood involve...

Question

One of the buffer systems used to control the pH of blood involves the equilibrium between H₂PO₄⁻ and H₂PO₄²⁻. The pKₐ for H₂PO₄²⁻ is 7.21.

Write the Henderson–Hasselbalch equation for this buffer system.

Accepted Answer

Hey, everyone, we're told that the ph in our stomach is regulated by a bicarbonate buffer system. The constituents of the buffer system are carbonic acid with a formula of H two co three and bicarbonate with a formula of HCO three minus. If carbonic acid has a PK A of 6.37 provide the Henderson Hassleback equation for this bicarbonate buffer. First, let's go ahead and recall our Henderson Hassleback equation which is going to be our PH is equal to our PK A plus the log of the concentration of our base over the concentration of our acid. Now that we've written this out, let's go ahead and plug in our components. So we have our PH which is equal to our PK A which we were told to be 6.37. Now we're going to go ahead and add the log of the concentration of our base, which we know to be our bicarbonate. Since this is the conjugate base of our weak acid carbonic acid, and we're going to divide this by the concentration of our carbonic acid and this will be our final answer. Now, I hope this made sense. And let us know if you have any questions.

One of the buffer systems used to control the pH of blood involves the equilibrium between H₂PO₄⁻ and H₂PO₄²⁻. The pKₐ for H₂PO₄²⁻ is 7.21. Write the Henderson–Hasselbalch equation for this buffer system.

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