When a metal is to be extracted from its ore, if the gangue associated with the ore is silica, then

Options

A. An acidic flux is needed
B. A basic flux is needed
C. Both acidic and basic flux are needed
D. Neither of them is needed

Explanation

To solve the question regarding the extraction of a metal from its ore when the gangue is silica (SiO2), we need to consider the nature of silica and its role in the metallurgical process.

### Step-by-Step Solution:

1. **Identify the Gangue**: The gangue associated with the ore is silica (SiO2). Gangue is the unwanted material that is present in the ore.

2. **Understand the Nature of Silica**: Silica (SiO2) is considered an acidic oxide. In metallurgy, acidic oxides typically react with basic fluxes during the smelting process.

3. **Determine the Type of Flux Needed**: Since silica is acidic, it requires a basic flux to react with it. Basic fluxes are used to combine with acidic impurities to form a slag that can be removed from the metal.

4. **Conclusion**: Therefore, when extracting a metal from an ore that has silica as the gangue, a basic flux is needed to facilitate the removal of the silica.

### Final Answer:
A basic flux is needed when the gangue associated with the ore is silica.

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