Extraction of copper is done using copper pyrites. After roasting, the ore is mixed with silica and coke and then smelted in a blast furnace. The matte obtained from the blast furnace is charged into a silica-lined converter. Some silica is also added, and a hot air blast is blown into the mixture to obtain blister copper, which is purified by electrorefining.
The chemical formula of copper pyrites is.

Options

A. `CuFeS_(2)`
B. `Cu_(2) O`
C. `Cu_(2) S`
D. `CuCO_(3).Cu(OH)_(2)`

Answer

**Step-by-Step Text Solution:**

1. **Identify the Ore**: The question states that copper is extracted using copper pyrites. Copper pyrites is a common ore of copper.

2. **Understand the Chemical Composition**: To find the chemical formula of copper pyrites, we need to analyze its components. Copper pyrites is primarily composed of copper (Cu), iron (Fe), and sulfur (S).

3. **Determine the Formula**: The chemical formula for copper pyrites is derived from its constituent elements. It contains one copper atom, one iron atom, and two sulfur atoms. Therefore, the formula can be written as:
\[ \text{Cu} + \text{Fe} + 2\text{S} \Rightarrow \text{CuFeS}_2 \]

4. **Evaluate the Options**: The question provides four options for the chemical formula:
- Option 1: CuFeS2
- Option 2: Cu2O
- Option 3: Cu2S
- Option 4: CuCO3·Cu(OH)2

5. **Select the Correct Option**: From the analysis, we see that the first option (CuFeS2) matches the derived formula for copper pyrites. The other options represent different compounds:
- Cu2O is cuprous oxide.
- Cu2S is copper sulfide (also known as copper glance).
- CuCO3·Cu(OH)2 is malachite.

6. **Conclusion**: Therefore, the correct chemical formula of copper pyrites is:
\[ \text{CuFeS}_2 \]

**Final Answer**: The chemical formula of copper pyrites is CuFeS2.

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