Metal can be obtained from metal oxide through the process of reduction.
Reduction:
- Reduction is a chemical reaction in which a substance gains electrons and decreases in oxidation state.
- In the context of obtaining metal from metal oxide, reduction involves the removal of oxygen from the metal oxide to obtain the pure metal.
- This is typically achieved by using a reducing agent, which donates electrons to the metal oxide, causing the oxygen to be removed.
- The reducing agent can be a more reactive metal, carbon, or even hydrogen gas, depending on the specific metal oxide being reduced.
- The reaction can be represented by the following general equation: Metal Oxide + Reducing Agent → Metal + By-products (such as carbon dioxide or water).
Other options:
- Liquefaction: This term refers to the process of converting a substance from a solid or a gas to a liquid state. It is not relevant to obtaining metal from metal oxide.
- Calcination: Calcination involves the heating of a substance to a high temperature in the absence of air or oxygen. It is typically used to drive off volatile substances or to cause decomposition. It is not directly related to obtaining metal from metal oxide.
- Roasting: Roasting is a process in which a substance is heated in the presence of oxygen. It is commonly used to convert sulfide ores into oxides. While roasting can be part of the overall process of obtaining metal from metal oxide, it is not the specific reaction by which metal is obtained.
Therefore, the correct answer is Option B: Reduction, as it specifically describes the reaction by which metal is obtained from metal oxide.

Each of this oxides are heated with carbon to obtain the metal. the metal oxide looses oxygen and gets reduced. thus carbon gains oxygen and gets oxidised.