Final answer:
The delta s sys for a condensation phase transition at 26.5°C with a delta h sys of -40.1 kJ/mol is -134 J/mol·K, indicating a decrease in the system's entropy during the process.
Step-by-step explanation:
The delta s sys (change in entropy of the system) for a condensation phase transition at 26.5°C for a compound that condenses at the same temperature with a delta h sys (change in enthalpy of the system) equal to -40.1 kJ/mol can be calculated using the following formula:
ΔSsys = ΔHsys / T
Where ΔHsys is the enthalpy change and T is the temperature in Kelvin.
The conversion of the temperature from Celsius to Kelvin is: T(K) = 26.5°C + 273.15 = 299.65K.
Substituting the given values:
ΔSsys = (-40.1 kJ/mol) / (299.65 K)
= -0.134 kJ/mol·K
= -134 J/mol·K
This value indicates the entropy decrease of the system during condensation, which is a process where the disorder of the system decreases as the gas becomes liquid.