Smelting involves reduction of metal oxide with:

Options

A. Carbon
B. Carbon Monoxide
C. Magnesium
D. Aluminium

Answer

### Step-by-Step Solution:

1. **Understanding Smelting**:
- Smelting is a metallurgical process used to extract metals from their ores. It involves heating the ore in the presence of a reducing agent.

2. **Identifying the Reducing Agent**:
- A reducing agent is a substance that donates electrons to another substance, reducing its oxidation state. In the context of smelting, the reducing agent is typically a form of carbon.

3. **Heating the Ore**:
- During smelting, the ore (which is a metal oxide) is heated to high temperatures. This high temperature is necessary to facilitate the reduction reaction.

4. **Reduction Reaction**:
- The metal oxide is reduced by the carbon. The carbon reacts with the metal oxide to form the metal and carbon monoxide (CO).
- For example, if we consider iron oxide (Fe2O3), the reaction can be represented as:
\[ Fe2O3 + 3C \rightarrow 2Fe + 3CO \]

5. **Formation of Carbon Dioxide**:
- The carbon monoxide produced can further react with oxygen to form carbon dioxide (CO2), especially if there is excess oxygen present:
\[ 2CO + O2 \rightarrow 2CO2 \]

6. **Conclusion**:
- Therefore, the process of smelting involves the reduction of metal oxide with carbon, which can be in the form of coke or charcoal.

### Final Answer:
Smelting involves the reduction of metal oxide with **carbon**.

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