Based on the calculations through the ICE table, the pH of the buffer solution is equal to 3.30.
<u>Given the following data:</u>
- Concentration of
= 0.55 M.
- Concentration of
= 0.75 M.
- Rate constant =

<h3>How to determine the pH of the buffer solution.</h3>
First of all, we would write the properly balanced chemical equation for this chemical reaction:

Initial cond. 0.55M 0 0.75M
-x x x
At equib. 0.55M - x 0 + x 0.75M + x
From the ICE table, the Ka for this chemical reaction is given by:
![K_{a}=\frac{[H^+][NO_2^+]}{HNO_2} \\\\H^+ = K_{a}\frac{[HNO_2]}{[NO_2^+]} \\\\H^+ = 6.8 \times 10^{-4} \times \frac{0.55}{0.75} \\\\H^+ = 6.8 \times 10^{-4} \times 0.733\\\\H^+ = 4.98 \times 10^{-4} \;M](https://tex.z-dn.net/?f=K_%7Ba%7D%3D%5Cfrac%7B%5BH%5E%2B%5D%5BNO_2%5E%2B%5D%7D%7BHNO_2%7D%20%5C%5C%5C%5CH%5E%2B%20%3D%20K_%7Ba%7D%5Cfrac%7B%5BHNO_2%5D%7D%7B%5BNO_2%5E%2B%5D%7D%20%5C%5C%5C%5CH%5E%2B%20%3D%20%206.8%20%5Ctimes%2010%5E%7B-4%7D%20%5Ctimes%20%5Cfrac%7B0.55%7D%7B0.75%7D%20%5C%5C%5C%5CH%5E%2B%20%3D%20%206.8%20%5Ctimes%2010%5E%7B-4%7D%20%5Ctimes%200.733%5C%5C%5C%5CH%5E%2B%20%3D%204.98%20%5Ctimes%2010%5E%7B-4%7D%20%5C%3BM)
Now, we can calculate the pH of the buffer solution:
![pH=-log[H^+]\\\\pH=-log[4.98 \times 10^{-4}]\\\\pH=-(-3.30)](https://tex.z-dn.net/?f=pH%3D-log%5BH%5E%2B%5D%5C%5C%5C%5CpH%3D-log%5B4.98%20%5Ctimes%2010%5E%7B-4%7D%5D%5C%5C%5C%5CpH%3D-%28-3.30%29)
pH = 3.30.
Alternatively, you can calculate the pH of this buffer solution by applying Henderson-Hasselbalch equation:

<u>Where:</u>
is acetate ion.
Read more on concentration here: brainly.com/question/3006391