Chemical Equilibrium

The chemical activity describes the effective concentration of a species in a mixture.

The chemical activity is unitless.

(fugacity = Flüchtigkeit)

The chemical activity describes the difference compared to the standard state, where the activity is 1

1

the mole fraction of the respective component

the respective partial pressure

for

The equilibrium constant is relatet to the change in standard forming enthalpy from educt to product ((delta)G0)

In equilibrium, the reaction quotient is constant over time and is equal to the equilibrium constant.

They are equal.

The enthalphy of a reaction is the difference in the enthalphy of educts and the products.

Elingham Diagram:

• determination of equilibrium oxygen pressure at a specific Temperature

• Connection line drawn between chosen point and intersection point of T line. Pressure can be read.

• O2 pressure from point O

• H2/H2O ratio from point H

• CO/CO2 ratio from point C

The dissociated Hydrogen (within a metal) is equal to the the equilibrium constant and the outer Hydrogen pressure.