1, and estimate the lowest decomposition temperature of Ag2O.

δRSMθ=δrhmθ/T

Because in general, rHmθ and rSmθ do not change with the change of temperature, the enthalpy of formation and standard entropy (298K data) of each substance can be obtained by looking up the table.

δrhmθ= 2δFHMθ(Ag，s)+ 1/2δFHMθ(O2，g)-δFHMθ(Ag2O，s)

= 0+0+-δFHMθ(Ag2O，s)

=-δFHMθ(Ag2O，s)

δRSMθ= 2 smθ(Ag，s) + 1/2 Smθ (O2，g)- Smθ (Ag2O，s)

The above can be found in the attached table in the book, and can be obtained by substitution calculation.

2. Find the equilibrium constant Kθ

δRGMθ=-RT ln kθ

δRGMθ=δrhmθ-TδRSMθ

RHmθ and rSmθ have been calculated in 1, so just substitute them.

3. Find p(O2)

According to the chemical equation:

[p(O2) / pθ ]^ 1/2 = Kθ

Kθ has been found in 2, and the partial pressure of oxygen can be obtained by substitution, and pθ is the standard pressure.