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how many milliliters of 0.202 m naoh should be added to 25.0 ml of 0.023 3 m salicylic acid (2-hydroxybenzoic acid) to adjust the ph to 3.50 (pka1

User Oyvindio
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1 Answer

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Final answer:

To adjust the pH of the salicylic acid solution, you can use the Henderson-Hasselbalch equation to determine the amount of NaOH needed. Calculate the number of moles of salicylic acid using the given volume and molarity, and substitute the values into the equation to solve for the ratio [A-]/[HA]. Use the balanced chemical equation to convert the ratio to moles of NaOH, and then to milliliters using the molarity of NaOH.

Step-by-step explanation:

To calculate the amount of NaOH needed to adjust the pH of the salicylic acid solution, we can use a similar approach as in Example 15.6.2. First, calculate the number of moles of salicylic acid using the given volume and molarity. Then, use the Henderson-Hasselbalch equation to determine the amount of NaOH needed to reach the desired pH.

Henderson-Hasselbalch equation: pH = pKa + log([A-]/[HA])

In this case, we want to reach a pH of 3.50, so substitute the values into the equation and solve for the ratio [A-]/[HA]. Finally, use the balanced chemical equation to convert the ratio to moles of NaOH, and then to milliliters using the molarity of NaOH.

User Spencer Booth
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