Select the correct statements (Ellingham diagram) :
A. When temperature is raised, a point will be reached where the graph crosses the `Delta_(f) G^(Ө) = 0` line. Below this temperature, the free energy of formation of the oxide is negative, so the oxide is stable
B. When the temperature is raised, a point will be reached where the graph crosses the `Delta_(f) G^(Ө) = 0` line. Above this temperature, the free energy of formation of the oxide is positive, and the oxide becomes instable, and should decompose into the metal and dioxygen.
C. Theoretically, all oxides can be decomposed to give the metal and dioxygen if a sufficiency high temperature can be attained.
D. Theoretically, all oxides cannot be decomposed to give the metal and dioxide if a sufficiently high temperature can be attained.
