Thermodynamic Equilibrium Models and Kinetics

The first law of thermodynamics states that energy cannot be created or destroyed (i.e., the total energy of a system is always constant). This means that if the internal energy of a reaction increases then there must be a concomitant uptake of energy usually in the form of heat. Enthalpy (H) is a parameter used to describe the energy of a system as heat 

Thermodynamics Chemical Kinetics Bioreaction Rates Mass Transfer 

The second law (at least one form of it) states that a spontaneous reaction is when there is a decrease in the system s free energy and an increase in the entropy (S). The Gibbs free energy (G) of a system is related to enthalpy and entropy by the following equation  

The chemical reaction for this, when the temperature of reactants and products are equal, is as follows  

The more negative AG°, the more spontaneous the system is, making it have a greater potential to react. For a given reaction the standard free energy AG°can be calculated by the following equation  

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