Question

The conversion of a zinc ore to zinc metal, the process of roasting involves:
(A) \[ZnC{O_3} \to ZnO\]
(B) \[ZnO \to ZnS{O_4}\]
(C) \[ZnS \to ZnO\]
(D) \[ZnS \to ZnS{O_4}\]

Answer 1

Hint: Roasting is a specific type of reaction which is used in the conversion of zinc ore to zinc metal. Roasting reaction involves sulphide ore to an oxide ore.

Complete Step-by-Step Solution:
According to the question, the zinc ore is converted to zinc metal using the Roasting process. As per definition, the roasting process involves conversion of sulphide ores to oxide ores. In roasting reactions, the sulphide ore of the metal is treated with oxygen. This results in the formation of the corresponding oxide ore, and also releases sulphur dioxide gas.
So when we consider the case of the conversion of a zinc ore to zinc metal using the process of roasting, then the corresponding sulphide ore of zinc is converted to its oxide ore. The sulphide ore of zinc, ZnS or commonly known as Zinc Blende ore is reacted with oxygen to give zinc oxide and releases sulphur dioxide gas. The chemical reaction for this process is given by:
\[2ZnS + 3{O_2}\xrightarrow{{roasting}}2ZnO + 2S{O_2}\]
In a simpler manner, the direct conversion can be represented as:
\[ZnS \to ZnO\]

Hence, Option C is the correct option.

Note: now to obtain zinc metal from this oxide ore, we need to perform a reduction reaction. The zinc oxide formed must be reacted with carbon and then heated. This results in the formation of pure Zinc metal and carbon monoxide gas.