The Ellingham diagram for zinc,magnesium and carbon converting into corresponding oxides is shown below.
At $........$ $^oC$ temperature,zinc and carbon have equal affinity for oxygen.

How is 'cast iron' different from 'pig iron'?

In the cyanide process for the extraction of $Ag$ from argentite,the oxidizing agent and reducing agent used are respectively:

Which of the following statements is incorrect?

Explain the role of thermodynamics in the extraction of elements. Or,explain how thermodynamics is helpful in the selection of a reducing agent for metallurgical operations.

Tin is obtained from cassiterite by reduction with coke. Use the data given below to determine the minimum temperature (in $K$) at which the reduction of cassiterite by coke would take place.
At $298 \ K$: $\Delta_{f}H^{\circ}(SnO_{2(s)}) = -581.0 \ kJ \ mol^{-1}$,$\Delta_{f}H^{\circ}(CO_{2(g)}) = -394.0 \ kJ \ mol^{-1}$
$S^{\circ}(SnO_{2(s)}) = 56.0 \ J \ K^{-1} \ mol^{-1}$,$S^{\circ}(Sn_{(s)}) = 52.0 \ J \ K^{-1} \ mol^{-1}$
$S^{\circ}(C_{(s)}) = 6.0 \ J \ K^{-1} \ mol^{-1}$,$S^{\circ}(CO_{2(g)}) = 210.0 \ J \ K^{-1} \ mol^{-1}$
Assume that the enthalpies and the entropies are temperature independent.