Adding Acid to buffered solution

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In summary, a buffered solution is a solution that can maintain a relatively constant pH when small amounts of acid or base are added. Adding acid to a buffered solution can help maintain a stable pH, as the acid in the buffer will react with the added acid to prevent a significant change. The Henderson-Hasselbalch equation can be used to calculate the change in pH when acid is added to a buffered solution. However, buffered solutions have limitations, as they can become overwhelmed with large amounts of acid and are only effective within a certain pH range.
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sunnyorange
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I need help:

A beaker with 200 of a 0.1M acetic acid buffer with a pH of 5.20 is sitting on a benchtop. A student adds 8.60 of a 0.380 solution to the beaker. How much will the pH change? The of acetic acid is 4.76.
 
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you need to be more specific about the units and species involved.
 
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Adding acid to a buffered solution will result in a change in the pH of the solution. In this situation, the addition of 8.60 mL of a 0.380 M solution will cause a decrease in the pH due to the increase in the concentration of acidic species. To determine the exact change in pH, we can use the Henderson-Hasselbalch equation, which relates the pH of a buffered solution to the pKa of the acid and the ratio of conjugate base to acid. In this case, the pKa of acetic acid is 4.76 and the initial concentration of acetic acid is 0.1 M. Adding 8.60 mL of a 0.380 M solution will result in a final concentration of 0.1 M + (8.60 mL x 0.380 M)/ (200 mL + 8.60 mL) = 0.103 M. Plugging these values into the Henderson-Hasselbalch equation, we can calculate the new pH of the solution to be approximately 5.08. Therefore, the pH will decrease by approximately 0.12 units. It is important to note that the actual change in pH may differ slightly due to factors such as temperature and the presence of other ions in the solution.
 

What is a buffered solution?

A buffered solution is a solution that resists changes in pH when small amounts of acid or base are added. It contains a weak acid and its conjugate base (or a weak base and its conjugate acid) which can neutralize any added acid or base, keeping the pH relatively constant.

Why would you add acid to a buffered solution?

Adding acid to a buffered solution can help maintain a stable pH. If the pH of the solution starts to increase, the acid in the buffer will react with the added acid, preventing a significant change in pH. This is useful in many scientific experiments and processes that require a specific and stable pH level.

What happens when acid is added to a buffered solution?

When acid is added to a buffered solution, the acid will react with the conjugate base of the buffer, forming the weak acid. This reaction will consume some of the added acid, preventing a large change in pH. The remaining acid will be neutralized by the buffer, maintaining the overall pH of the solution.

How do you calculate the change in pH when acid is added to a buffered solution?

The Henderson-Hasselbalch equation is commonly used to calculate the change in pH when acid is added to a buffered solution. The equation takes into account the initial pH, the pKa of the weak acid in the buffer, and the concentration of the buffer components. By plugging these values into the equation, you can determine the new pH of the solution after the addition of acid.

What are the limitations of a buffered solution when adding acid?

Buffered solutions are effective at resisting changes in pH when small amounts of acid are added. However, if a large amount of acid is added, the buffer may become overwhelmed and the pH will change significantly. Additionally, buffers are only effective within a certain pH range, so if the added acid falls outside of this range, the buffer may not be able to neutralize it effectively.

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