Acid Base Titrations II: Potentiometric And Indicator T

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Title- Experiment #9- Acid Base Titrations II: Potentiometric and Indicator Titrations Introduction- In this experiment, the reactions of three different acids with a strong base are studied by observing how the pH of the solution changes as the titrant is added. A plot of pH versus amount of titrant added will be constructed. Such a curve is called a pH titration curve. The equivalence point of the reaction will be determined from an analysis of the pH titration curve, and by the use of acid-base indicators. The pH measures the solution whether it is acidic and basic. The pH of the solution could be determined by using the following equation, pH= -log[H+]. It could also be determined by finding the pOH= -log[OH-] and then subtracting …show more content…
The lower the pH, the more acidic the solution is. The higher the pH is, the more basic (less acidic) the solution is. However, by titrating a weak acid with a strong base, the pH of the solution would be depending on how low or high the concentration and ionization are. A strong acid dissociates completely in a solution, meanwhile a weak acid will ionize partially. The equivalence point is an important factor because it can help determine the pH of a solution where the amount of acid equals the amount of base. Also, each indicator has its own pH range. For example, there are indicators that only change color when pH is equivalent to a specific pH that belong within that …show more content…
A buret is then rinsed with ~5mL of the 0.1 M NaOH solution and then filled with the solution with no air bubbles present in the tip of the buret. The Hydrochloric acid is titrated with the 0.1 M NaOH in increments given in the data sheet; mixing well at each point and wait until the pH stabilizes. The pH is recorded at each increment and the electrode is rinsed with distilled water and placed back in the beaker with distilled water. The pipet is rinsed with distilled water and then with 5mL of 0.1 M Acetic acid. Next, 25mL of 0.1 M Acetic acid is pipetted into a 100mL beaker. The 0.1 M Acetic acid is titrated with the 0.1 M NaOH in increments given in the data sheet; mixing well at each point and wait until the pH stabilizes. The pH is recorded at each increment and the electrode is rinsed with distilled water and placed back in the beaker with distilled water. Then, 25mL of 0.1 M Acetic acid is pipetted into a 250mL Erlenmeyer flask. Next, 2-3 drops of the proper indicator is added. The 0.1 M Acetic acid is titrated with the NaOH slowly until a stable color change persists, which is the equivalence point. The buret reading is taken to the nearest 0.01mL. The pipet is rinsed with distilled water and then with 5mL of 0.05 phosphoric acid (H3PO4). Finally, 25mL of 0.05 phosphoric acid (H3PO4) is pipetted into a 100mL beaker. The 0.05 phosphoric acid (H3PO4) is titrated with the 0.1 M NaOH in increments given in the

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