The main reactions that occur in the blast furnace during iron extraction from hematite are:

a. Fe2O3  + 3CO → 2Fe + 3CO2
b. FeO + SiO2 →  FeSiO3
c. Fe2O+ 3C  \(\xrightarrow[]{}\) 2Fe + 3CO
d. CaO + SiO2 \(\xrightarrow[]{}\) CaSiO3
 

Choose the correct option:
1. a and b
2. b and c
3. c and d
4. a and d

HINT: Fe2O3 is first reduced to Fe3O4 and then to FeO
Explanation:
STEP 1:
In the extraction of iron from haematite ore following reactions take place.
(i) Fe2O3 + 3CO2 Fe + 3CO2
This reaction represents a reduction of Fe2O3 to Fe.
(ii) CaO + SiO2  Formation of slag CaSiO3Slag
STEP 2: 
The reactions are as follows: