Answer :
Final answer:
The molar entropy (∆Sm) of vaporization for methanol is 126.8 J/(mol∙K). This value represents the change in entropy when one mole of liquid methanol is vaporized at a specific temperature.
Explanation:
The vapor pressure of CH₃OH(l) at 25 °C is 125 torr. The enthalpy of vaporization (∆Hvap) for methanol is 37.9 kJ/mol.
Methanol (CH₃OH) is a liquid at 25 °C. Its vapor pressure, which is the pressure exerted by the vapor phase when the liquid and vapor are in equilibrium, is 125 torr. This means that at this temperature, the liquid methanol will start to evaporate and form a vapor with a pressure of 125 torr.
The enthalpy of vaporization (∆Hvap) for methanol is 37.9 kJ/mol. This value represents the amount of energy required to convert one mole of liquid methanol into vapor at its boiling point.
The standard enthalpy change (∆H°) for the vaporization of methanol is -238.7 kJ/mol. This value indicates the enthalpy change when one mole of liquid methanol is vaporized at 1 atm and at the standard temperature of 25 °C.
The molar entropy (∆Sm) of vaporization for methanol is 126.8 J/(mol∙K). This value represents the change in entropy when one mole of liquid methanol is vaporized at a specific temperature.
These values provide important thermodynamic information about the behavior of methanol as a liquid and its tendency to vaporize at 25 °C.
