Solving Henderson-Hasselbalch Equation: Buffer Question

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In summary, a buffer is a solution that can resist changes in pH by utilizing a weak acid and its conjugate base, or a weak base and its conjugate acid. In biochemistry, buffers are important for maintaining the pH of biological systems to ensure proper functioning of enzymes and other biomolecules. They work by using Le Chatelier's principle to prevent large changes in pH. The Henderson-Hasselbalch equation is used to calculate the pH of a buffer solution, taking into account the concentrations and dissociation constant of the weak acid. To prepare a buffer solution, a specific ratio of weak acid and conjugate base (or weak base and conjugate acid) is mixed together, either directly or through a titration method.
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BIOCHEM: buffer question!

You have a sample of 50 mL of 0.2 M formic acid, which has a pKa of 3.75 (Ka = 1.78x10-4). How much 2 M KOH must be added to adjust the pH of the sample to 3.75?

The correct answer is 2.5mL

I tried using the henderson hasslebach equation and I just cannot wrap my head around how to go about solving it. It should be simple but i get into way to many steps and still come out with the wrong answer HELPPP
 
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What happens in the solution of the formic acid when you add KOH?
 

What is a buffer?

A buffer is a solution that is able to resist changes in pH when small amounts of acid or base are added to it. It is made up of a weak acid and its conjugate base, or a weak base and its conjugate acid. This allows the buffer to maintain a relatively constant pH level even when other substances are introduced.

Why are buffers important in biochemistry?

Buffers are important in biochemistry because they help maintain the pH of biological systems, which is critical for the proper functioning of enzymes and other biomolecules. Without buffers, small changes in pH could disrupt important biochemical reactions and potentially harm living organisms.

How do buffers work?

Buffers work by utilizing the principle of Le Chatelier's principle. When an acid or base is added to a buffer, the buffer's components will react with the added substance to maintain a relatively constant pH. The weak acid or base will either donate or accept protons, preventing large changes in pH.

What is the Henderson-Hasselbalch equation?

The Henderson-Hasselbalch equation is a mathematical formula used to calculate the pH of a buffer solution. It takes into account the concentrations of the weak acid and its conjugate base, as well as the dissociation constant of the acid.

How do you prepare a buffer solution?

To prepare a buffer solution, you will need to mix a weak acid and its conjugate base (or a weak base and its conjugate acid) in a specific ratio. This ratio will depend on the desired pH of the buffer solution and the dissociation constant of the weak acid. The components can be mixed together directly, or you can use a titration method to prepare the buffer solution.

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