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 ΔG for the oxidation of ethanol, we need to determine the overall reaction and then use the Gibbs free energy change of formation values (ΔGf) for ethanol and its products.
The overall reaction for the oxidation of ethanol can be represented as follows:
C2H5OH + 3O2 -> 2CO2 + 3H2O
The ΔGf values (standard Gibbs free energy change of formation) for ethanol (-174 kJ/mol), carbon dioxide (-394 kJ/mol), and water (-286 kJ/mol) are needed.
First, we convert the given mass of glucose (1.00 g) to moles of ethanol. The molar mass of glucose is 180.16 g/mol and ethanol has a molar mass of 46.07 g/mol:
1.00 g glucose × (1 mol glucose/180.16 g glucose) × (2 mol ethanol/1 mol glucose) = 0.0111 mol ethanol
Next, we use ΔGf values to calculate the ΔG for the reaction:
ΔG = (2ΔGf for CO2 + 3ΔGf for H2O) - (ΔGf for ethanol)
ΔG = (2 × -394 kJ/mol + 3 × -286 kJ/mol) - (-174 kJ/mol)
Calculating this equation gives:
ΔG = (-788 kJ + (-858 kJ + 522 kJ) - (-174 kJ)
ΔG = -1532 kJ + 174 kJ
ΔG = -1358 kJ
Finally, we convert the value to kJ/g by dividing ΔG by the number of moles of ethanol (0.0111 mol) obtained earlier:
ΔG/g = -1358 kJ/ 0.0111 mol = -122,613 kJ/mol
Therefore, the ΔG for the oxidation of ethanol is approximately -122,613 kJ/mol or -111,013 kJ/g.
Note: The calculated value is an estimation, and small deviations due to rounding off may occur.