Question

Among the reactions (a) – (d), the reaction(s) that does/do not occur in the blast furnace during the extraction of iron is/are:

(a) $\mathrm{CaO}+{\mathrm{SiO}}_2\to {\mathrm{CaSiO}}_3$

(b) $3{\mathrm{Fe}}_2{\mathrm{O}}_3+\mathrm{CO}\to 2{\mathrm{Fe}}_3{\mathrm{O}}_4+{\mathrm{CO}}_2$

(c) $\mathrm{FeO}+{\mathrm{SiO}}_2\to {\mathrm{FeSiO}}_3$

(d) $\mathrm{FeO}\to \mathrm{Fe}+(1/2){\mathrm{O}}_2$

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

Answer 1

The correct option is C

(c) and (d)

The explanation for correct option:

C (c) and (d)

• In the extraction of iron, Iron oxide $\left(\mathrm{FeO}\right)$ does not react with silica ${\mathrm{SiO}}_2$ hence, option (c) is incorrect for the process.
• As represented in option (d), Iron oxide $\left(\mathrm{FeO}\right)$ does not disassociate to form iron and oxygen in the process of extraction of iron.

Explanation for incorrect options:

A (a)

• In the extraction of iron, Calcium oxide $\mathrm{CaO}$ is obtained by thermal decomposition of Calcium carbonate ${\mathrm{CaCO}}_3$ react with silica (sand) impurities in hematite to form slag which is Calcium silicate ${\mathrm{CaSiO}}_3$.

B (d)

• As represented, Iron oxide $\left(\mathrm{FeO}\right)$ does not disassociate to form iron and oxygen in the extraction of iron.

D (a) and (d)

• In extraction of iron, Calcium oxide $\mathrm{CaO}$ obtained by thermal decomposition of Calcium carbonate ${\mathrm{CaCO}}_3$ react with silica (sand) impurities in haematite to form slag which is Calcium silicate ${\mathrm{CaSiO}}_3$.
• Hence, option (a) is correct.
• But, Iron oxide $\left(\mathrm{FeO}\right)$ does not disassociate to form iron and oxygen in the extraction of iron.
• Hence, option (d) is incorrect.

Hence option (c) is correct, statements (c) and (d) are not correct for the extraction of iron.