Which of the following is chalcopyrite?

Options

A. `CuFeS_2`
B. `FeS_2`
C. `kMgCl3.6H_2O`
D. `Al_2O3.2H_2O`

Answer

To determine which of the given options is chalcopyrite, we need to analyze each option based on their chemical formulas and identify which one corresponds to chalcopyrite.

### Step-by-Step Solution:

1. **Identify the Options**:
- Option 1: CuFeS2
- Option 2: FeS2
- Option 3: KMgCl3.6H2O
- Option 4: Al2O3.2H2O

2. **Analyze Option 1 (CuFeS2)**:
- The chemical formula CuFeS2 represents chalcopyrite. Chalcopyrite is a copper iron sulfide mineral and is an important copper ore.

3. **Analyze Option 2 (FeS2)**:
- The chemical formula FeS2 represents iron pyrite, commonly known as fool's gold. This is not chalcopyrite.

4. **Analyze Option 3 (KMgCl3.6H2O)**:
- The chemical formula KMgCl3.6H2O represents a hydrated magnesium chloride mineral known as cornelite. This is not chalcopyrite.

5. **Analyze Option 4 (Al2O3.2H2O)**:
- The chemical formula Al2O3.2H2O represents bauxite, which is an aluminum ore. This is also not chalcopyrite.

6. **Conclusion**:
- After analyzing all the options, we find that the only option that corresponds to chalcopyrite is Option 1: CuFeS2.

### Final Answer:
The correct option that represents chalcopyrite is **Option 1: CuFeS2**.

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