Question

Ellingham diagrams are mainly used to determine:

• A. Phase equilibrium
• B. Oxide stability
• C. Reaction kinetics
• D. Diffusion coefficients

Hint:

The lower a line is on the Ellingham diagram, the more stable the oxide is, meaning it is harder to reduce but has a stronger affinity for oxygen.

Answer 1

The Correct Option is B

Picture a graph where every metal oxide has its own line showing how easily it forms as temperature rises. A line sitting lower on this graph means that oxide holds together more strongly and is harder to break apart, so it is more stable. This is the whole point of an Ellingham diagram, it lets you compare oxides side by side and instantly see which one is tougher to reduce and which one gives up its oxygen easily to a more reactive metal. The diagram says nothing about how fast a reaction proceeds or how atoms move inside the solid, it is purely about which oxide wins the stability contest. So the diagram is used to judge oxide stability.