Roasted copper pyrite on smelting with sand produces

Options

A. `FeSiO_3 ` as fusible slag and ` Cu_2 S ` as matte
B. ` CaSiO_3 ` as infusible slag and ` Cu_2O ` as matte
C. ` Ca_3 (PO_4)_2 ` as fusible slag and ` Cu_2 S ` as matte
D. ` Fe_3 (PO_4)_2 ` as infusible slag and ` Cu_2S ` as matte

Explanation

To solve the question "Roasted copper pyrite on smelting with sand produces," we will follow these steps:

### Step-by-Step Solution:

1. **Identify the Composition of Copper Pyrite**:
- Copper pyrite is a mineral that contains copper, iron, and sulfur. Its chemical formula is \( \text{CuFeS}_2 \).

2. **Understand the Roasting Process**:
- Roasting involves heating the copper pyrite in the presence of oxygen. This process converts the sulfide into an oxide and releases sulfur dioxide gas.
- The reaction can be represented as:
\[ 2 \text{CuFeS}_2 + 5 \text{O}_2 \rightarrow 2 \text{Cu}_2\text{O} + 2 \text{FeO} + 4 \text{SO}_2 \]

3. **Smelting with Sand**:
- Smelting is the process of extracting metal from its ore by using heat and a chemical reducing agent.
- In this case, we are smelting the roasted copper pyrite with sand (which is primarily silica, \( \text{SiO}_2 \)).
- The silica acts as a flux to remove impurities.

4. **Formation of Slag**:
- During smelting, the copper oxide reacts with silica to form a slag, which is a mixture of metal oxides and impurities.
- The reaction can be represented as:
\[ \text{Cu}_2\text{O} + \text{SiO}_2 \rightarrow \text{2Cu} + \text{SiO}_2 \]
- The slag formed is primarily \( \text{SiO}_2 \) and other metal silicates.

5. **Final Products**:
- The final products of the smelting process are:
- Copper metal (\( \text{Cu} \))
- Slag (which is primarily \( \text{SiO}_2 \) and other metal silicates)

### Conclusion:
Roasted copper pyrite on smelting with sand produces copper metal and slag (silica).

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