Answer: The entropy change of the ethyl acetate is 133. J/K
Explanation:
To calculate the number of moles, we use the equation:
[tex]\text{Number of moles}=\frac{\text{Given mass}}{\text{Molar mass}}[/tex]
Given mass of ethyl acetate = 398 g
Molar mass of ethyl acetate = 88.11 g/mol
Putting values in above equation, we get:
[tex]\text{Moles of ethyl acetate}=\frac{398g}{88.11g/mol}=4.52mol[/tex]
To calculate the entropy change for different phase at same temperature, we use the equation:
[tex]\Delta S=n\times \frac{\Delta H_{fusion}}{T}[/tex]
where,
[tex]\Delta S[/tex] = Entropy change = ?
n = moles of ethyl acetate = 4.52 moles
[tex]\Delta H_{fusion}[/tex] = enthalpy of fusion = 10.5 kJ/mol = 10500 J/mol (Conversion factor: 1 kJ = 1000 J)
T = temperature of the system = [tex]84.0^oC=[84+273]K=357K[/tex]
Putting values in above equation, we get:
[tex]\Delta S=\frac{4.52mol\times 10500J/mol}{357K}\\\\\Delta S=132.9J/K[/tex]
Hence, the entropy change of the ethyl acetate is 133. J/K
