Consider a biochemical reaction that is taking place in a 0.1 M buffer. The initial pH is 7.4, and the pKa of the buffer is 7.2. If, in a final reaction volume of 1.0 mL, 10 micromol of protons are generated, what would be the final pH of the solution?

The pH of the solution is 7,22

Explanation:

Using the Henderson–Hasselbalch equation we can find the pH of the solution.

First, we need to find the concentrations of [A-] and [HA]

Now we apply the antilogarithm function to both sides of the equation

using the previous equation and the ratio [A-] + [HA] = 0.1 we proceed to apply a system of equations to find the values of [HA] and [A-].

after solving the system of equations

[A-]=0,0613

[HA]= 0,0387

After the 10 micromol of protons are generated the protons will reduce [A-]  and increase [HA].

[H+] =

[H+] = 0,01M

now, the new value of pH is