Question

In ellingham diagram,the slope of the curve of the formation of metal oxide is​

Answer 1

Answer:

it is proportional to ΔS.

Answer 2

Answer:

Explanation:

Ellingham diagram compares the ability of reducing agents to extract a particular metal from its oxide. The lines in Ellingham's diagram signifies about the Gibb's free energy change for the reaction of the formation of oxide. A reaction which has more positive Gibb's energy, will not be spontaneous.

As we have considered the reaction

M + O2 →MO

if the reaction is non spontaneous, it means that MO will decompose to M and O. Actually we have considered the reverse reaction. we are concerned with the reduction of metal fro metal oxide, we assume the reverse reaction to find the same. Mainly we want to know that MO + X → M + XO

Considering the reverse reaction M + O2 →MO

we see that Oxygen gas has more entropy than solid metal oxide, Thus entropy decreases and hence Gibb's free energy change is becoming more positive , with increasing temperature. We are not concerned with the boiling or melting of any oxide or metal. Increasing temperature does not always mean that the substance is boiling or melting.

The lines in diagram considers the free energy formation of the various metal oxides. The line or metal having , most positive Gibb's energy change will be unstable and hence it will prefer to stay as M and O2. Thus the other metal (X)can easily reduce that metal oxide(MO) to metal(M) and oxygen.

For e.g. by looking into the diagram , we can see that aluminum can reduce the zinc oxide to zinc metal as the free energy of formation of Al2O3 is more negative(it wants to stay as aluminum oxide than aluminium) and that of ZnO is less and thus it will prefer to stay as Zn and oxygen.