Fe2O3 (Ferric oxide), found as hematite ore, is an insoluble solid, and H2SO4 (Sulfuric acid) is a strong inorganic acid. Let us study how their reaction occurs.
The reaction of H2SO4 with Fe2O3 is an acid-base reaction. H2SO4 is highly corrosive and a powerful dehydrating agent that is highly useful in organic synthesis. Fe2O3 is red-brown in appearance and a stable oxide of iron.
Here, we will discuss some reaction parameters like enthalpy, molecular forces, and the feasibility of the H2SO4+Fe2O3 reaction.
What is the product of H2SO4 and Fe2O3
Fe2(SO4)3 (Ferric sulfate) and H2O (water molecules) are produced in the reaction of H2SO4 + Fe2O3.
H2SO4 + Fe2O3 → Fe2(SO4)3 + H2O
What type of reaction is H2SO4 + Fe2O3
H2SO4 + Fe2O3 is a neutralization reaction. Here, Fe2O3 is a base that neutralizes sulfuric acid and forms salt.
How to balance H2SO4 + Fe2O3
The H2SO4 + Fe2O3 reaction is balanced using the following steps.
H2SO4 + Fe2O3 → Fe2(SO4)3 + H2O
- The reactants and the products involved in the reaction are identified and counted.
- With the use of coefficients, the charges and elements are balanced. Before H2SO4 and H2O, a coefficient of 3 is added.
- Thus we get the balanced equation as
- 3H2SO4 + Fe2O3 → Fe2(SO4)3 + 3H2O
H2SO4 + Fe2O3 titration
Gravimetric analysis is used for the titration of Fe2O3. It is a type of analytical method in which the estimation of the analyte is done by the mass of the solid which is carried out using the following process.
Crucible, burette, glass rod, funnel, beaker, filter paper, burner
- Burette is filled with Ferrous ammonium sulfate solution. From this, 10 ml of the sulfate solution is taken into the volumetric flask and diluted with distilled water up to the mark.
- The resultant solution is transferred to a dry beaker to get the homogenous solution.
- 25 ml of the diluted solution is taken in another beaker and 50 ml of distilled water is added to it with the help of a cylinder.
- After the addition of 5 ml of H2SO4 to the solution, heat it on the burner using a wire gauge.
- 3 ml of nitric acid (HNO3) is added dropwise to the heating solution with constant stirring. HNO3 will oxidize Iron and the color of the solution changes to yellow.
- 0.2 grams of NH4Cl (ammonium chloride) is further added to the heated solution along with 10 ml of 1:1 ammonia solution until the reddish brown precipitate of Fe(OH)3 appears.
- The solution is heated to get the precipitate to settle down and boil off the excess of ammonia.
- Filter the solution using Whatman paper and transfer the precipitate carefully to the filter paper.
- Precipitate is washed with 2% ammonium nitrate solution and hot water and the precipitate is dried and heated strongly in the crucible.
- Weight of the dried precipitate (Fe2O3) is taken and used in calculations for the estimation of the Iron.
H2SO4 + Fe2O3 net ionic equation
The net ion equation of the H2SO4 + Fe2O3 reaction is
Fe2O3(s) + 2H+(aq) → 2Fe3+(aq)+ 2SO42-(aq) + 3H2O(l)
The ionic equation is deduced using the following steps
- The balanced equation for Fe2O3 + H2SO4 is written in the first step,
- Fe2O3 + H2SO4 → Fe2(SO4)3 + 3H2O
- The phases (solid, gas, liquid, or aqueous) is indicated for all the substituents.
- Fe2O3(s) + H2SO4(aq) → Fe2(SO4)3(aq) + 3H2O(l)
- Splitting of the strong-electrolytes is done in the next step. Since Fe2O3 is solid and H2O is a weak-electrolyte, they will not split. The equation now becomes,
- Fe2O3(s) + 2H+(aq)+SO42-(aq) → 2Fe3+(aq)+ 3SO42-(aq) + 3H2O(l)
- The spectator-ions are canceled out and the net equation is
- Fe2O3(s) + 2H+(aq) → 2Fe3+(aq)+ 2SO42-(aq) + 3H2O(l)
H2SO4 + Fe2O3 conjugate pairs
H2SO4 + Fe2O3 will not constitute a conjugate acid-base pair as they do not conjugate with each other.
- The conjugate base of H2SO4 is SO42-.
- Fe2O3 is an oxide so no conjugate pair concept is applied here.
H2SO4 and Fe2O3 intermolecular forces
- Hydrogen bonding, dipole-dipole interactions and dispersion forces are observed in H2SO4 molecules where Hydrogen bonding is most prominent.
- Electrostatic force of attraction is found in Fe2O3 molecules as it is ionic in nature attributed to the small size of Fe3+ ion and electronegativity difference between Fe and O.
H2SO4 + Fe2O3 reaction enthalpy
H2SO4 + Fe2O3 reaction enthalpy is -59.68 KJ/mol. The calculation of the enthalpy is done using the values below,
∆Hf°(reaction) = ∆Hf°(products) – ∆Hf°(reactants)
= -3620.8 – (-3561.12)
= -59.68 KJ/mol
Is H2SO4 + Fe2O3 a buffer solution
Fe2O3 + H2SO4 will not function as a buffer as here sulfuric acid is used which is a strong acid.
Is H2SO4 + Fe2O3 a complete reaction
Fe2O3 + H2SO4 is a complete reaction as a complete neutralization is observed by giving off the salt Fe2(SO4)3 and water as the products.
Is H2SO4 + Fe2O3 an exothermic or endothermic reaction
Fe2O3 + H2SO4 is an exothermic reaction as it gives off heat during the reaction. Also, the negative value of enthalpy (-59.68 KJ/mol) indicates the same.
Is H2SO4 + Fe2O3 a redox reaction
Fe2O3 + H2SO4 is not a redox reaction because the oxidation of the substituents remains same throughout the reaction.
Is H2SO4 + Fe2O3 a precipitation reaction
H2SO4 + Fe2O3 is not a precipitation reaction as the salt formed [Fe2(SO4)3] is soluble in water.
Is H2SO4 + Fe2O3 reversible or irreversible reaction
H2SO4 + Fe2O3 reaction is an irreversible reaction as the Iron sulfate formed will not react with water to give the reactants due to the lesser reactivity of hydrogen than Fe.
Is H2SO4 + Fe2O3 displacement reaction
H2SO4 + Fe2O3 is a double displacement reaction.
The reaction between H2SO4 and Fe2O3 is exothermic and occurs in an irreversible manner. Fe2O3 is a major source for the production of iron and is of high importance when it comes to dye and cosmetic industry.