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A chemistry student needs to determine the pH of a solution using a pH meter. The student has to prepare a buffer solution of pH 7.0 using 0.1M acetic acid and 0.1M sodium acetate. The student is then required to measure the pH of the prepared buffer solution using a pH meter and record the observations. Finally, the s

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To help the student determine the pH of the solution, we will first calculate the theoretical pH of the buffer solution using the Henderson-Hasselbalch equation. Then, we will guide the student through the process of preparing the buffer solution, measuring its pH using a pH meter, and comparing the observed pH value with the calculated value.1. Calculate the theoretical pH of the buffer solution:The Henderson-Hasselbalch equation is given by:pH = pKa + log  [A-]/[HA] For acetic acid, the pKa value is 4.74. Since the student is using equal concentrations of acetic acid  HA  and sodium acetate  A- , both 0.1M, the equation becomes:pH = 4.74 + log  0.1/0.1 pH = 4.74 + log  1 pH = 4.74 + 0pH = 4.74The calculated pH of the prepared buffer solution is 4.74.2. Prepare the buffer solution:To prepare 1L of the buffer solution, the student should mix 0.1 moles of acetic acid and 0.1 moles of sodium acetate in a 1L volumetric flask. To do this, they should:a. Measure 0.1 moles of acetic acid  CH3COOH  using a volumetric pipette and transfer it to the volumetric flask.b. Measure 0.1 moles of sodium acetate  CH3COONa  using a weighing balance and transfer it to the volumetric flask.c. Fill the flask with distilled water up to the 1L mark and mix the solution thoroughly.3. Measure the pH of the prepared buffer solution:a. Calibrate the pH meter using standard buffer solutions with known pH values  e.g., pH 4, 7, and 10 .b. Rinse the electrode with distilled water and gently blot it dry with a tissue.c. Immerse the electrode in the prepared buffer solution and wait for the pH reading to stabilize.d. Record the observed pH value.4. Compare the observed pH value with the calculated pH value:The student should compare the pH value obtained using the pH meter with the calculated pH value of 4.74. Any deviations observed could be due to:a. Errors in the preparation of the buffer solution, such as inaccurate measurements of acetic acid or sodium acetate.b. Inaccurate calibration of the pH meter.c. Contamination of the buffer solution or the pH electrode.The student should discuss these potential sources of error and suggest ways to minimize them in future experiments.

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