Questions: What was the freezing point depression in acetic acid caused by the benzoic acid? Determine the answer by estimating the difference in degrees (to the nearest 0.1°C) between the flattest portions of the curves in Trial 1 and Trial 3. Mark the area on the graph with an arrow (↓) to show where the temperature difference estimate was made.

Solution Steps

To solve the problem of determining the freezing point depression in acetic acid caused by benzoic acid, we need to analyze the temperature data from two trials: Trial 1 (pure acetic acid) and Trial 3 (acetic acid with benzoic acid). The goal is to find the difference in the freezing points between these two trials.

Examine the graph provided for both Trial 1 and Trial 3. The freezing point is typically identified as the flattest portion of the cooling curve, where the temperature remains relatively constant as the substance transitions from liquid to solid.

Estimate the freezing point for each trial by identifying the temperature at the flattest portion of each curve:

• Trial 1 (Pure Acetic Acid): Identify the temperature at the flattest portion of the curve.
• Trial 3 (Acetic Acid with Benzoic Acid): Identify the temperature at the flattest portion of the curve.

Calculate the freezing point depression by finding the difference between the freezing points of Trial 1 and Trial 3: \[ \Delta T_f = T_{\text{Trial 1}} - T_{\text{Trial 3}} \] Round the result to the nearest \(0.1^{\circ} \mathrm{C}\).

Final Answer