Determination of Change in Enthalpy for Reacting Species and Mixtures

4 DETERMINATION OF CHANGE IN ENTHALPY FOR REACTING SPECIES AND MIXTURES 

Here we have assumed there is no latent heat term in the enthalpy expression, although it should be added as needed if not already accounted for in the heat of formation. Similar expressions can be written for the change in any intensive thermodynamic parameter of interest. For example, consider generic parameter x, where x can represent s, u, or g, that 

Example 3.7 Change in Enthalpy for Reacting Gas-Phase Mixture Find the change in enthalpy per mole of hydrogen for combustion of a 50% hydrogen-50% oxygen mixture (by mole) at 298 K. The final product is water vapor and oxygen at 1000 K. 

Entropy (S) The concept of entropy is typically more difficult to grasp than most other thermodynamic parameters, yet it is an important part of the science of fuel cells to 

Practically, we need an expression for calculating entropy in terms of regularly measurable thermodynamic quantities. We cannot inspect a system to determine the number of available quantum microstates or buy an entropy meter at the store like we can purchase 

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Determination of Change in Enthalpy for Reacting Species and Mixtures 83... 

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