How many possible chemical reactions
are there ?
Do we need to know G or Ks as a
function of T for all of these ?
If so approach not useful.
Introduce the concept of the Formation
Definition: A Formati
Conservation of Atoms
Chemical reaction in a closed vessel:
2HI H 2 I2
then : dn HI 2dn H 2
dn HI 2dn I 2
dn HI dn H 2 dn I 2
convention : reactants (LHS) negative
dn H 2 dn I 2
degree of advancement
If the reaction is known a single v
dT 0 dT
Invalid at point of phase change
If there is a chemical reaction:
n constant - frozen heat capacity
ni varies - use equilibrium concentrations
Q not a state variable: must specify path
Thermodynamics of Gases
Until now (almost) all relations have
been generally applicable.
For high speed flows or combustion we
are generally interested in gases.
Lets concentrate on gas phase
Start off with a simple model, a perfect