the process of respiration, glucose is oxidized completely. In fermentation, O2 is absent, and glucose is broken down into Co2 and H2o.
Calculate delta g for respiration of 1.00 g of glucose
Calculate delta g for fermentation of 1.00 g of glucose.
My answers:
-16.0 kJ and -1.26 kJ
what I need help with is:
Calculate delta g for oxidation of the ethanol from part C.
answer in kJ/g..............thanks!
To calculate the ΔG (change in free energy) for the oxidation of ethanol, you need to consider the reaction:
C2H5OH + O2 → CO2 + H2O
First, you need to determine the standard ΔG° values for each reactant and product in the reaction. These values can be found in thermodynamic tables. Given that the values are usually given per mole and you want the answer per gram, you will need to convert these values as well.
The standard ΔG° values for ethanol (C2H5OH) and carbon dioxide (CO2) are approximately:
ΔG°(C2H5OH) = -276 kJ/mol
ΔG°(CO2) = -394 kJ/mol
Next, you need to determine the stoichiometric coefficients of the reactants and products in the reaction:
C2H5OH: -1
O2: -1
CO2: 1
H2O: 1
Now, you can calculate the moles of ethanol used by dividing the mass of ethanol (which is 1.00 g) by its molar mass (which is approximately 46.07 g/mol). Hence,
moles of C2H5OH = 1.00 g / 46.07 g/mol
Next, you can calculate the ΔG for the oxidation of ethanol using the formula:
ΔG = Σ(ΔG° products) - Σ(ΔG° reactants)
ΔG = (1 mol CO2 × ΔG°(CO2)) + (1 mol H2O × ΔG°(H2O)) - (moles of C2H5OH × ΔG°(C2H5OH))
Finally, substitute the given values into the equation and calculate:
ΔG = (1 mol × -394 kJ/mol) + (1 mol × 0 kJ/mol) - (moles of C2H5OH × -276 kJ/mol)
Convert the moles of ethanol obtained earlier to run the calculation:
ΔG = (1 mol × -394 kJ/mol) + (1 mol × 0 kJ/mol) - (0.0217 mol × -276 kJ/mol)
Finally, divide the obtained value by the mass of ethanol (1.00 g) to obtain the answer in kJ/g:
ΔG = (-394 kJ) + (0 kJ) - (-60.192 kJ) / 1.00 g
ΔG = -16.808 kJ / 1.00 g
Therefore, the ΔG for the oxidation of ethanol is approximately -16.808 kJ/g.