Which of the following factors is of no significance for roasting sulphide ores to the oxides and not subjecting the sulphide ores to carbon reduction directly?

Options

A. Metal sulphides are thermodynamically more stable than `CS_2`
B. `CO_2` is thermodynamically more stable than `CS_2`
C. Metal sulphides are less stable than the corresponding oxides
D. `CO_2` is more volatile than `CS_2`

Answer

C

Explanation

`DeltaG` is positive for reduction of metal sulphides by carbon, whereas it is negative for reduction of metal oxides by carbon. So,`CO_2` is thermodynamically more stable than `CS_2`, thus metal sulphides are more stable than metal oxides.