What is the change in entropy that occurs in the system when 45.0 g of acetone (C₃H₆O) freezes at its melting point (-94.8 °C)? Use Table 11.9 for the heats of fusion.

Verified step by step guidance

1. Identify the formula for calculating the change in entropy (\( \Delta S \)) during a phase change: \( \Delta S = \frac{q_{\text{rev}}}{T} \), where \( q_{\text{rev}} \) is the heat absorbed or released during the phase change and \( T \) is the temperature in Kelvin.
2. Convert the given mass of acetone (45.0 g) to moles using its molar mass (58.08 g/mol).
3. Use the heat of fusion for acetone from Table 11.9 to calculate \( q_{\text{rev}} \). The heat of fusion is the amount of energy required to change a substance from solid to liquid at its melting point.
4. Convert the temperature from Celsius to Kelvin by adding 273.15 to the given melting point (-94.8 °C).
5. Substitute the values of \( q_{\text{rev}} \) and \( T \) into the entropy change formula to find \( \Delta S \).