the thermodynamics of ethanol gibbs free energy the thermodynamic data for the combustion of ethanol is…

the thermodynamics of ethanol gibbs free energy the thermodynamic data for the combustion of ethanol is given below. δs_comb = -217.9 j/k δh_comb = -1,325 kj/mol c₂h₅oh calculate the standard free energy for the combustion of ethanol. what is the standard free energy change (δg⁰), in kj/mol, for the combustion of ethanol? a. 63600 kj/mol b. -1330 kj/mol c. -1260 kj/mol d. -1390 kj/mol
Answer
Answer:
B. -1330 kJ/mol
Explanation:
Step1: Convert entropy - unit
Convert $\Delta S_{comb}=- 217.9\ J/K$ to $kJ/K$. $\Delta S_{comb}=-217.9\ J/K=-0.2179\ kJ/K$
Step2: Use Gibbs - free energy formula
The formula for Gibbs free energy is $\Delta G^0=\Delta H_{comb}-T\Delta S_{comb}$. At standard conditions, $T = 298\ K$. $\Delta G^0=-1325\ kJ/mol-(298\ K\times(- 0.2179\ kJ/K))$
Step3: Calculate the result
$\Delta G^0=-1325\ kJ/mol + 64.9342\ kJ/mol\approx - 1330\ kJ/mol$