# DoITPoMS

Partial pressure of reacting gas

Using equations (15) we can see that the equilibrium constant is related to the partial pressures of reacting gases:

$${K_P} = {{{p_C}} \over {{p_A}{p_B}}}$$

for the reaction $${\rm{A}} + {\rm{B}} \to {\rm{C}}$$. (Remember that these pressures must be related to a standard state.)

For a metal oxidation reaction ,

2M (s) + O2 (g) = 2MO (s) ,

the equilibrium constant has the form

$${K_P} = {1 \over {p_{{O_2}}^{}}}$$

$${\left. {{p_{{O_2}}}} \right|_{eq.,T}} = \exp {{\Delta G^\circ } \over {RT}}$$