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Questions for the preparation for the lesson.
1. Basic concepts of thermodynamics. Status function. Internal energy. Work
and heat are two forms of energy transfer.
2. Types of thermodynamic systems (isolated, closed, open). Standard state.
3. The first law of thermodynamics. Enthalpy. Standard enthalpy of sub-
stance formation, standard enthalpy of substance combustion. The standard en-
thalpy of the reaction.
4. Hess’s law and its consequences. Application of the first law of thermo-
dynamics to biosystems.
5. The second law of thermodynamics. Reversible and irreversible process-
es in the thermodynamic sense. Entropy.
7. The energy of Gibbs. Forecasting the direction of spontaneous process-
es in isolated and closed systems; the role of enthalpy and entropy factors. Ther-
modynamic conditions of equilibrium.
8. The standard Gibbs energy of substance formation. The standard Gibbs
energy of the reaction. Examples of exergonic and endergonic processes occur-
ring in the body.
9. Chemical equilibrium. Reversible and irreversible in the direction of the
reaction. The constant of chemical equilibrium. Thermodynamic equilibrium
conditions in isolated and closed systems.
10. Equations of the chemical reaction isotherm. Prediction of displacement
of chemical equilibrium.
Input test-control on the topic «Chemical thermodynamics».
Homework exercises.
1. 100 grams of cod contain, on the average, 11.6 g of proteins and 0.3 g of
fats. Determine the calorie content of the cod portion of 200 grams.
Answer
:
103.02 kcal.
2. The thermal effect of the reaction SO
2
(g) + 2H
2
S (g) = 3S (t) + 2H
2
O (g)
is 234.5 kJ. Determine the standard enthalpy of formation for H
2
S (g), if the
∆H value of formation for SО
2
(g), Н
2
О (g)are –297, –286 kJ/mol, respectively.
Answer
: –20.25 kJ/mol.
3. The heat of combustion of glucose is 2816 kJ/mol, the heat of combustion
of ethanol is equal to 1236 kJ/mol. Calculate the thermal effect of the biochemical
process of glucose fermentation.
Answer
: 344 kJ/mol.