Which reaction does not occurs in the blast furnace in the metallurgy of Fe:
` a. CaO + SiO_2 rarr CaSiO_3`
`b. Fe_(2)O_(3) + CO rarr Fe_(3)O_(4) + CO_2`
` c. FeO + SiO_2 rarr FeSiO_3 `
` d. FeO rarr (heat) Fe + 1/2 O_2`

Options

A. A and B
B. A, B and C
C. C and D
D. A, B, C and D

Explanation

To determine which reaction does not occur in the blast furnace during the metallurgy of iron, we will analyze each option provided in the question.

### Step 1: Analyze Reaction A
**Reaction A:** \( \text{CaO} + \text{SiO}_2 \rightarrow \text{CaSiO}_3 \)

In the blast furnace, calcium oxide (CaO) reacts with silicon dioxide (SiO2) to form calcium silicate (CaSiO3), which acts as a slag. This reaction is indeed part of the process to remove impurities.

**Conclusion:** Reaction A occurs in the blast furnace.

### Step 2: Analyze Reaction B
**Reaction B:** \( \text{Fe}_2\text{O}_3 + \text{CO} \rightarrow \text{Fe}_3\text{O}_4 + \text{CO}_2 \)

This reaction represents the reduction of iron(III) oxide (Fe2O3) by carbon monoxide (CO) to form magnetite (Fe3O4). This reduction process is a key step in the extraction of iron in the blast furnace.

**Conclusion:** Reaction B occurs in the blast furnace.

### Step 3: Analyze Reaction C
**Reaction C:** \( \text{FeO} + \text{SiO}_2 \rightarrow \text{FeSiO}_3 \)

This reaction suggests that iron(II) oxide (FeO) reacts with silicon dioxide (SiO2) to form iron silicate (FeSiO3). However, in the blast furnace, FeO is typically reduced further by CO to produce iron (Fe) and CO2. The formation of iron silicate is not a common reaction in the blast furnace.

**Conclusion:** Reaction C does not occur in the blast furnace.

### Step 4: Analyze Reaction D
**Reaction D:** \( \text{FeO} \rightarrow \text{Fe} + \frac{1}{2} \text{O}_2 \)

This reaction implies that iron(II) oxide (FeO) decomposes into iron and oxygen gas. In the blast furnace, FeO is reduced by CO rather than decomposing directly. Therefore, this reaction is not representative of the processes occurring in the blast furnace.

**Conclusion:** Reaction D does not occur in the blast furnace.

### Final Conclusion
The reactions that do not occur in the blast furnace are **C** and **D**. However, since the question asks for one reaction that does not occur, we can select **C** as the primary answer.

### Answer:
**C. \( \text{FeO} + \text{SiO}_2 \rightarrow \text{FeSiO}_3 \)** does not occur in the blast furnace.

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