Consider the following chemical reaction : aFe₂O₃(s) + bCO(g) → cFe(s)

Consider the following chemical reaction :
aFe₂O₃(s) + bCO(g) → cFe(s) + dCO₂
In the balanced chemical equation of the above, which of the following will be the values of the coefficients a, b, c and d respectively?

3, 2, 3, 1
1, 3, 2, 3
2, 3, 3, 1
3, 3, 2, 1
This question was previously asked in
UPSC CDS-1 – 2018
The given chemical reaction is the reduction of iron(III) oxide by carbon monoxide: Fe₂O₃(s) + CO(g) → Fe(s) + CO₂(g). To balance the equation aFe₂O₃ + bCO → cFe + dCO₂, we balance the atoms of each element:
– Fe: 2a = c
– O: 3a + b = 2d
– C: b = d
Substituting b=d into the oxygen balance: 3a + d = 2d, which gives 3a = d.
So we have the relationships: c = 2a, b = 3a, d = 3a.
To find the smallest integer coefficients, we can set a=1.
Then, b = 3(1) = 3, c = 2(1) = 2, d = 3(1) = 3.
The coefficients are a=1, b=3, c=2, d=3. This corresponds to option B.
– Balancing chemical equations involves ensuring the number of atoms of each element is the same on both the reactant and product sides.
– Coefficients represent the relative number of molecules or moles involved in the reaction.
– Balancing is achieved by using stoichiometric coefficients in front of the chemical formulas.
This reaction is a key process in the blast furnace for smelting iron ore, where iron(III) oxide is reduced by carbon monoxide produced from the combustion of coke. The balanced equation shows that one molecule of iron(III) oxide reacts with three molecules of carbon monoxide to produce two atoms of iron and three molecules of carbon dioxide.