Thermodynamic Principles of Metallurgy — Prelims Questions

Which of the following statements regarding the Ellingham diagram for metal oxides is INCORRECT?

Calculate the minimum temperature (in Kelvin) at which the reduction of $\text{FeO}$ by carbon becomes spontaneous, given the following data: For $\text{Fe}(s) + \frac{1}{2}\text{O}_2(g) \rightarrow \text{FeO}(s)$: $\Delta H^\circ = -268\,\text{kJ/mol}$, $\Delta S^\circ = -63\,\text{J/mol·K}$ For $\text{C}(s) + \frac{1}{2}\text{O}_2(g) \rightarrow \text{CO}(g)$: $\Delta H^\circ = -110\,\text{kJ/mol}$, $\Delta S^\circ = +88\,\text{J/mol·K}$

On an Ellingham diagram, the line for the formation of $\text{CO}$ from $\text{C}$ and $\text{O}_2$ has a negative slope. What is the primary reason for this characteristic?

Which of the following metals cannot be reduced by carbon at any practically achievable temperature, based on Ellingham diagram principles?

For a reaction to be spontaneous at all temperatures, which of the following conditions must be met?

Given the following Ellingham diagram, if the line for the formation of $\text{MO}$ is above the line for the formation of $\text{CO}$ at temperature $T_1$, and below the line for the formation of $\text{CO}$ at temperature $T_2$ ($T_2 > T_1$), what can be inferred about the reduction of $\text{MO}$ by carbon?

Consider the formation of $\text{MgO}$ and $\text{ZnO}$ from their respective metals and oxygen. On an Ellingham diagram, the line for $\text{MgO}$ is significantly lower than that for $\text{ZnO}$ across a wide temperature range. What does this imply?