In: Chemistry
The normal boiling point of ethanol, C2H5OH, is 78.3 °C, and its molar enthalpy of vaporization is 38.56 kJ/mol. What is the change in entropy in the system when 68.3 g of C2H5OH(g)2at 1 atm condenses to liquid at the normal boiling point?
The normal boiling point of ethanol, C2H5OH, is 78.3 °C,
T = 78.3 + 273 = 351.3K
The molar enthalpy of vaporization is 38.56 kJ/mol
Hvap = 38.56 kJ/mol = 38560J/mole
S = Hvap /T
= 38560J/mole/351.3K = 109.76J/mole-K
no of moles of ethanol = W/G.M.Wt
= 68.3/46 = 1.485 moles
S = 109.76J/mole-K * 1.485 moles
= 163J/K >>>>answer
The change in entropy in the system = 163J/K >>>>answer