15 Facts on H2SO4 + Sb2S3: What, How To Balance & FAQs

Antimony trisulfide is a sulfide mineral with the molecular formula Sb₂S₃. Let us inspect various features related to its reaction with sulfuric acid.

Sb₂S₃ + H₂SO₄ is an uncommon reaction that forms an acid with gas evolution. Sb₂S₃ commonly occurs in nature as crystalline stibnite or antimonite. It appears as a grayish to black orthorhombic crystal structure. It is immiscible in water that melts at 550⁰C. H₂SO₄ is an effective oxidizing and dehydrating agent.

This article shall discuss significant aspects of its reaction with Sb₂S₃, such as the products, the reaction type, redox mechanism, etc.

What is the product of H₂SO₄ and Sb₂S₃

Antimonic acid (H₃SbO₄), sulfur dioxide (SO₂) and water (H₂O) are major products obtained when antimony trisulfide (Sb₂S₃) reacts with sulfuric acid (H₂SO₄).

Sb₂S₃ (aq) + 11H₂SO₄ (aq) —> 2H₃SbO₄ (aq) + 14SO₂ (g) + 8H₂O (l)

What type of reaction is H₂SO₄ + Sb₂S₃

H₂SO₄ + Sb₂S₃ is a single-displacement reaction, also known as single replacement reaction.

How To Balance H₂SO₄ + Sb₂S₃

The balanced chemical equation for H₂SO₄ + Sb₂S₃ is:

Sb₂S₃ + 11H₂SO₄ = 2H₃SbO₄ + 14SO₂ + 8H₂O

The hit-and-trial method is used to balance the given chemical equation, and the steps are as follows:

• The number of atoms of elements for reactants and products is counted and tabulated in the first step.

Atoms	Reactant Side	Product Side
Antimony	2	1
Sulfur	4	1
Oxygen	4	7
Hydrogen	2	5

• The element antimony, Sb, is balanced by multiplying the compound H₃SbO₄ by coefficient 2.
• The hydrogen atoms are balanced by multiplying compounds H₂O and H₂SO₄ by coefficients 8 and 11, respectively.
• Finally, sulfur is balanced by multiplying the compound SO₂ by coefficient 14, which also balances the unbalanced oxygen atoms.
• Thus the balanced chemical equation is:
• Sb₂S₃ + 11H₂SO₄ = 2H₃SbO₄ + 14SO₂ + 8H₂O

H₂SO₄ + Sb₂S₃ Titration

Titration of Sb₂S₃ against H₂SO₄ is not practicable because antimony trisulfide behaves as an antimony salt rather than a base, yielding no significant results.

H₂SO₄ + Sb₂S₃ Net Ionic Equation

The net ionic equation for the reaction H₂SO₄ + Sb₂S₃ is:

22 H⁺ + 11 SO₄^2- + 2 Sb³⁺ + 3 S^2-= 6 H⁺ + 2 SbO₄^3- + 14 SO₂ + 16 H⁺ + 8 O^2-

Following are the steps to derive the net ionic equation:

• The balanced chemical equation is written, representing their respective physical states.
• Sb₂S₃ (aq) + 11H₂SO₄ (aq) = 2H₃SbO₄ (aq) + 14SO₂ (g) + 8H₂O (l)
• The compounds existing in aqueous phases are split into ions, and thus the balanced net ionic equation after dissociation is as follows:
• 22 H⁺ + 11 SO₄^2- + 2 Sb³⁺ + 3 S^2- = 6 H⁺ + 2 SbO₄^3- + 14 SO₂ + 16 H⁺ + 8 O^2-

H₂SO₄ + Sb₂S₃ Conjugate Pairs

H₂SO₄ + Sb₂S₃ has the following conjugate pairs:

• The conjugate base of H₂SO₄ after donating a proton is HSO₄^–.
• The conjugate base of H₃SbO₄ is H₂SbO₄^–.
• The conjugate acid of H₃SbO₄ is SbO₄^3-.

H₂SO₄ + Sb₂S₃ Intermolecular Forces

• Van der waals dispersion forces, dipole-dipole interactions and hydrogen bonding are the intermolecular forces between the molecules of H₂SO₄.
• Ionic forces are involved in H₃SbO₄ molecules as it is ionic in nature.

H₂SO₄ + Sb₂S₃ Reaction Enthalpy

The enthalpy of the reaction H₂SO₄ + Sb₂S₃ has not been determined because no thermodynamic process has been reported.

Is H₂SO₄ + Sb₂S₃ a Buffer Solution

H₂SO₄ + Sb₂S₃ mixture will not form a buffer as H₂SO₄ is used. It is a strong acid that does not meet the conditions for buffer formation.

Is H₂SO₄ + Sb₂S₃ a Complete Reaction

H₂SO₄ + Sb₂S₃ is a complete reaction where Sb₂S₃ combines with H₂SO₄ to form the complete product H₃SbO₄, with SO₂ released as gas.

Is H₂SO₄ + Sb₂S₃ an Exothermic or Endothermic Reaction

H₂SO₄ + Sb₂S₃ is an exothermic reaction due to the liberation of heat during the reaction process.

Is H₂SO₄ + Sb₂S₃ a Redox Reaction

H₂SO₄ + Sb₂S₃ is a redox reaction as a change in oxidation state is observed wherein Sb in +3 oxidation state changes to +5 state as we move from reactants to products.

Is H₂SO₄ + Sb₂S₃ a Precipitation Reaction

H₂SO₄ + Sb₂S₃ is a precipitation reaction, as H₃SbO₄ is obtained as a residue.

Is H₂SO₄ + Sb₂S₃ Reversible or Irreversible Reaction

The reaction H₂SO₄ + Sb₂S₃ is irreversible in nature because the products generated cannot be reversed to form the reactants under the same reaction conditions.

Is H₂SO₄ + Sb₂S₃ Displacement reaction

H₂SO₄ + Sb₂S₃ is an example of a single-displacement reaction as sulfur gets displaced from H₂SO₄ by Sb.

Conclusion

This article summarizes the reaction between H₂SO₄ and Sb₂S₃, where antimonic acid is formed as a major product along with sulfur dioxide and water. Antimonic acid, in its crystalline form, may be utilized in regeneration of heteropolyacid catalysts. Sulfur dioxide is mostly employed as a reducing agent.