Use the Henderson–Hasselbalch equation to calculate the pH of a buffer solution that is 0.25 M in formic acid (HCO2H) and 0.50 M in sodium formate (HCO2Na).

Video transcript

Hello everyone today? We have the following question, calculate the ph of a buffer solution. That is 0.2 75 moller glycolic acid and 750.550 molar sodium. Glad the PK The PK of glycolic acid is 3.83. So this is a buffer solution. Why is it a buffer solution? Well it's a buffer solution because it is composed of a weak acid and its conjugate base. So since it is a buffer we can use what's known as the Henderson Hasselbach equation to determine its ph so the ph is equal to the P. K. A. Plus the log of our conjugate acid divided by the concentration of our acid. So we have the P. K. Which was 3.83 plus the log The concentration for our conjugate base which in this example would be our glycol eight And that was 0.550 moller. We're gonna divide that by the concentration of our like folic acid which was our acid. And that was 0.275 dolar. And when we do that we end up with a ph equal to 4.13 as our final answer. And with that we've answered the question overall. I hope this helped. And until next time