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.
AtomsReactant SideProduct Side
Antimony21
Sulfur41
Oxygen47
Hydrogen25
Count of number of atoms
  • 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 SO42- + 2 Sb3+ + 3 S2-= 6 H+ + 2 SbO43- + 14 SO2 + 16 H+ + 8 O2-

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 SO42- + 2 Sb3+ + 3 S2- = 6 H+ + 2 SbO43- + 14 SO2 + 16 H+ + 8 O2-

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 SbO43-.
H2SBO4
Conjugate base of H3SbO4

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.