Among the reactions (a) - (d) , the reactions (s) that does /do not occur in the blast furnace during the extraction of iron is / are
(a) `CaO+SiO_2rarrCaSiO_3`
(b) `3Fe_2O_3+COrarr2Fe_3O_4+CO_2`
(c) `FeO+SiO_2rarrFeSiO_3`
(d) `FeOrarrFe+1/2O_2`

Options

A. (c) and (d)
B. (a) and (d)
C. (a)
D. (b)

Answer

To determine which reactions do not occur in the blast furnace during the extraction of iron, let's analyze each reaction step by step.

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

- This reaction represents the formation of slag (calcium silicate) from calcium oxide (lime) and silicon dioxide (silica).
- This reaction occurs in the blast furnace as it helps in removing impurities from iron ore.

**Conclusion**: Reaction (a) occurs in the blast furnace.

### Step 2: Analyze Reaction (b)
**Reaction (b)**: \( 3\text{Fe}_2\text{O}_3 + \text{CO} \rightarrow 2\text{Fe}_3\text{O}_4 + \text{CO}_2 \)

- This reaction involves the reduction of iron(III) oxide (hematite) to iron(II,III) oxide (magnetite) using carbon monoxide.
- This is a typical reaction that occurs in the blast furnace during the reduction of iron oxides.

**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 represents the formation of iron silicate from iron(II) oxide and silicon dioxide.
- However, in the blast furnace, iron(II) oxide is typically reduced to iron metal rather than forming iron silicate.

**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 suggests the direct reduction of iron(II) oxide to iron metal with the release of oxygen.
- In the blast furnace, iron(II) oxide is reduced by carbon monoxide or carbon, not by releasing oxygen.

**Conclusion**: Reaction (d) does not occur in the blast furnace.

### Final Answer
The reactions that do not occur in the blast furnace during the extraction of iron are **(c)** and **(d)**.

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