Q. 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?
A) Metal sulphides are thermodynamically more stable than $CS_{2}$
B) $CO_{2}$ is bthermodynamically more stable than $CS_{2}$
C) Metal sulphides are less stable than the corresponding oxides
D) $CO_{2}$is more volatile than $CS_{2}$
Explanation
(c)
$2MS + C \rightarrow 2M + CS_{2}\ \ \ \ \ \ \ \mathrm{\Delta}G_{1} =$positive
$2MO + C \rightarrow 2M + CO_{2}\ \ \ \ \ \ \ \mathrm{\Delta}G_{2} =$negative
The value of $\mathrm{\Delta}G$ for the9 formation of $CO_{2}$is negative, $ie$, it is thermodynamically more than $CS_{2}.$Also metal sulphides are thermodynamically more stable than $CS_{2}.$Metal sulphides are more stable than the corresponding oxides, so they are roasted to convert into less stable oxides
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.