Discover The 15 Incredible Facts On H2SO3 + BaO Reaction

H2SO3 is an inorganic weak acid. The molecule of H2SO3 can found in gas phase. BaO is a strong base. Let us try to understand some features of the reaction between H2SO3 and BaO.

H2SO3 is a colorless substance with odor of sulphur. H2SO3 is a white solid with corrosive property. BaO is also known as baria and it is a hygroscopic non-flammable compound. Generally BaO is used as drying agent in various chemical reactions.

In this article, we will try to study about some frequently asked questions about the H2SO3 and BaO reaction like the nature of the reaction, the product of the reaction, enthalpy, intermolecular forces etc.

What is the product of H2SO3 + BaO?

Barium sulfite (BaSO3) and water (H2O) are the products of the reaction between sulfurous acid (H2SO3) and barium oxide (BaO).

H2SO3 + BaO = BaSO3 + H2O

What type of reaction is H2SO3 + BaO?

The H2SO3 + BaO reaction is an example of neutralization reaction between weak acid and strong base. H2SO3 is a weak acid and BaO is a strong base.

How to balance H2SO3 + BaO?

The number of individual atoms (H, S, O, Ba) in the reactants and products should be the same in a balanced chemical equation. To get the balanced equation we have to follow some steps.

  • Here, it is found that four individual elements are present. Hence, in the first step, each molecule is labeled as A, C, D, and E.
  • Now, the reaction looks like this, A H2SO3 + C BaO = D BaSO3 + E H2O
  • All the same elements’ coefficients are rearranged by their stoichiometric proportion, and we get, H = 2A + 0C = 0D + 2E, S = 1A + 0C= 1D + 0E, O = 3A + 1C = 3D + 1E, Ba = 0A + 1C = 1D + 0E.
  • Then by calculating the coefficient and variables by the Gaussian elimination process, we get the required values of A, C, D, and E.
  • It is found as, A = 1, C = 1, D = 1, and E = 1.
  • Now, it is found that the number of moles of each element is both sides is equal.
Symbol of ElementsMoles in reactant sideMoles in product side
Moles of elements in reactant and product side
  • Hence, the overall balanced equation will be H2SO3 + BaO = BaSO3 + H2O

H2SO3 + BaO titration

The strength of H2SO3 can be determined by performing titration between a weak acid and strong base.

Apparatus used

Burette, 20 ml pipette, conical flask, burette stand, beakers, measuring cylinder, measuring flask, and funnel.

Titre and titrant

In H2SO3 + BaO titration reaction, H2SO3 is the titre and BaO is the titrant.


Phenolpthalein is used as the indicator to detect the end point in this acid base neutralization reaction.


  • Standardized solution of BaO is taken in the burette.
  • 20 ml of H2SO3 of unknown strength is taken in a conical flask by using 20 ml pipette.
  • 1-3 drops of Phenolpthalein indicator is added to acid in the conical flask.
  • From burette BaO was added dropwise into the conical flask until the pink colour is observed at the endpoint.
  • This process was repeated at least 3-4 times to get accurate reading.
  •  The strength of H2SO3 is calculated by using the formula, N1V1 = N2V2.

H2SO3 + BaO net ionic equation

The H2SO3 + BaO reaction has the following kind of net ionic equation,

H+ +HSO3 + Ba2+ + O2- = Ba2+ + SO32- + H+ +OH

  • H2SO3 is dissociated into H+ and HSO3 ions.
  • BaO dissociates into Ba2+ + O2- ions.
  • BaSO3 dissociates into Ba2+ and SO32- ions.
  • H2O dissociates into H+ and OH ions.
  • Hence, the net ionic equation of H2SO3 + BaO is H+ +HSO3 + Ba2+ + O2- = Ba2+ + SO32- + H+ +OH

H2SO3 + BaO conjugated pairs

The H2SO3 + BaO has the following net conjugate pairs

  • The conjugate base of H2SO3 is HSO3 (by donating a proton).
  • The conjugate acid of BaO is Ba2+ (according to Lewis concept).
  • The conjugate acid of H2O is H3O+.

H2SO3 + BaO intermolecular forces

H2SO3 + BaO has the following intermolecular forces,

  • H2SO3 has electrostatic force of attraction between protons and sulphite ions.
  • BaO has covalent bonding.

H2SO3 + BaO reaction enthalpy

The standard reaction enthalpy of the reaction between H2SO3 + BaO is -286349.39 kJ/mol, which is a negative value.

MoleculeEnthalpy (of formation) kJ/mol
Enthalpy of formation of molecules
ethanol 3 1
Potential energy diagram of reactants and products
  • Enthalpy change = (sum of enthalpy of formation of products) – (sum of enthalpy of formation of reactants) = [-1030 + (-) 285820] – [52.89 + (-) 553.50] = – 286349.39 kJ/mol.

Is H2SO3 + BaO a buffer solution?

The H2SO3 + BaO solution is not a buffer solution because H2SO3 is a weak acid but BaO is not the conjugate base of that acid.

Is H2SO3 + BaO a complete reaction?

The H2SO3 + BaO reaction is the complete reaction as the products of the reaction, BaSO3 and H2O both are stable substances.

Is H2SO3 + BaO an exothermic or endothermic reaction?

The H2SO3 + BaO reaction is exothermic as a negative enthalpy change value is obtained, and when these two elements react with each other, heat is released.

Is H2SO3 + BaO a redox reaction?

The H2SO3 + BaOreaction is not a redox reaction as the oxidation states of the elements (Ba, S, H) not change during the reaction.

Is H2SO3 + BaO a precipitation reaction?

The H2SO3 + BaO reaction is not a precipitation reaction because though BaSO3 is slightly soluble in water, no precipitate is formed during this reaction.

What Are the Basics of Synthesis Reactions?

A synthesis reaction beginner’s guide explains the basics of this chemical process. Synthesis reactions involve the combination of two or more substances to form a new compound. These reactions require energy and often result in the release of heat. Understanding the fundamentals allows beginners to navigate through the intricacies of synthesis reactions.

Is H2SO3 + BaO reversible or irreversible?

The H2SO3 + BaO reaction is irreversible because in this reaction the products, BaSO3 and H2O, do not convert back to the reactants.

Is H2SO3 + BaO a displacement reaction?

The H2SO3 + BaO reaction is a double displacement reaction as the ions of the reactants,H2SO3 and BaO are swapped and produce new compounds as products.


The reaction of H2SO3 with BaO is neutralization reaction which is characterized by the formation of a salt and water. H2SO3 is used in food, cosmetic industries. BaSO3 molecule has both ionic and covalent bond.