15 Facts on H2SO3 + LiOH: What, How To Balance & FAQs

Sulfurous acid can easily react with a strong base like lithium hydroxide at normal conditions. Let us see the reaction mechanism between H₂SO₃ and LiOH in this article.

LiOH or lithium hydroxide is a strong inorganic alkali metal base and it can easily release hydroxide ions. H₂SO₃ is a strong inorganic acid that can easily release protons on hydrolysis. In H₂SO₃ there will be one double-bonded O atom present along with two hydroxyl groups attached with sulfur.

As the reaction occurs between a strong acid and a strong base so it does not require any catalyst or temperature. Let us discuss the mechanism of the reaction between sulfuric acid and iron, the reaction enthalpy, the type of reaction, product formation, etc in the following part of the article.

1. What is the product of H₂SO₃ and LiOH?

Lithium sulfite is formed as a major product when H₂SO₃ and LiOH are reacted together along with some water molecules also produced.

H₂SO₃ + LiOH = Li₂SO₃ + H₂O

2. What type of reaction is H₂SO₃ + LiOH?

H₂SO₃ + LiOH reaction is an example of a double displacement reaction along with redox and precipitation reactions. It is also an acid-base neutralization reaction.

3. How to balance H₂SO₃ + LiOH?

H₂SO₃ + LiOH = Li₂SO₃ + H₂O, we have to balance the equation in the following way,

• Labelling all the reactants and products by the required number of alphabets.
• First, we labeled all the reactants and products by A, B, C, and D as there are four different atoms obtained for this reaction and the reaction looks like,
• A H₂SO₃ + B LiOH = C Li₂SO₃ + D H₂O
• Equating all the Coefficients for all the same type of elements by rearranging them.
• After the rearrangement of all the coefficients of the same elements by their stoichiometric proportion we get,
• H = 2A = B = 2D, S = A = C, O = 3A = B = 3C = D, Li = B = C.
• Using Gaussian elimination to determine the coefficient values
• Using the Gaussian elimination and equating all the equations we get, A = 1, B = 2, C = 1, and D = 2.
• Now write the whole equation in the balanced form
•  The overall balanced equation will be,
• H₂SO₃ +2 LiOH = Li₂SO₃ + 2 H₂O

4. H₂SO₃ + LiOH titration

To standardize the acid as well as a base we can perform a titration between LiOH and H₂SO₃

Apparatus used

We need a burette, conical flask, burette holder, volumetric flask, and beakers for this titration.

Titre and titrant

H₂SO₃ versus LiOH, H₂SO₃ acts as a titrant taken in the burette and the molecule to be analyzed is LiOH taken in a conical flask.

Indicator

The whole titration is done in acidic pH and for acid-base reaction, Phenolphthalein is the most suitable indicator which can be used.

Procedure

The burette was filled with unstandardized H₂SO₃ and LiOH was taken in a conical flask along with the respective indicator. H₂SO₃ is added dropwise to the conical flask and the flask was shaking constantly. After a certain time when the endpoint arrived LiOH changes its color.

5. H₂SO₃+ LiOH net ionic equation

The net ionic equation between H₂SO₃ + LiOH is as follows,

H⁺(aq.) + OH^–(aq.) + SO₂(g) + Li⁺(aq.) + OH^–(aq.) = 2Li⁺(aq.) + SO₃^2-(aq.) + H⁺(aq.) + OH^–(aq.)

• To derive the net ionic equation the following steps are required,
• First, we ionized all the possible compounds in their existing state like aqueous or gaseous form.
• After that, H₂SO₃ will be ionized in proton and sulfite ions as it is a strong electrolyte
• After that LiOH, is also dissociated to Li⁺ ion and OH^– as it is a strong base.
• After that, the product Li₂SO₃ dissociated into Li⁺ and SO₃^2-.
• Water is also ionized to H⁺ and OH^-.
• SO₂ is an existing gaseous form so it cannot be ionized.

6. H₂SO₃ + LiOH conjugate pairs

In the reaction, H₂SO₃ + LiOH conjugate pairs will be the corresponding de-protonated and protonated form of that particular species which are listed below-

• Conjugate pair of H₂SO₃ = SO₃^2-
• Conjugate pair of OH^– = H₂O
• Conjugate pairs of SO₄^2- = H₂SO₄

7. H₂SO₃ and LiOH intermolecular forces

The intermolecular force between H₂SO₃ is an electrostatic, covalent force. In lithium hydroxide, there will be ionic bonds present along with electrostatic force.

8. H₂SO₃ + LiOH reaction enthalpy

In the reaction, H₂SO₃ + LiOH reaction enthalpy is -83.99 KJ/mol which can be obtained by the formula enthalpy of products – enthalpy of reactants, and here the change in enthalpy is negative.

9. Is H₂SO₃ + LiOH a buffer solution?

The reaction between H₂SO₃ + LiOH gives a buffer solution of lithium sulfite which is salt but can control the pH.

10. Is H₂SO₃ + LiOH a complete reaction?

H₂SO₃ + LiOH is the complete reaction because it gives one major product Li₂SO₃ along with water. The reaction takes need some time to complete until all the reactants completely reacted the products are not formed.

11. Is H₂SO₃ + LiOH an exothermic or endothermic reaction?

H₂SO₃ + LiOH is exothermic in terms of thermodynamics first law. So, the reaction released more energy and temperature to the surroundings, Where, δH is always negative.

12. Is H₂SO₃ + LiOH a redox reaction?

H₂SO₃ + LiOH is a redox reaction because in this reaction Li gets reduced whereas sulfur gets oxidized. In this reaction, LiOH acts as an oxidizing agent whereas H₂SO₃ acts as a reducing agent.

13. Is H₂SO₃ + LiOH a precipitation reaction

H₂SO₃ + LiOH is a precipitation reaction because Li₂SO₃ gets precipitated in the solution at acidic pH and is not soluble in the reaction mixture.

14. Is H₂SO₃ + LiOH reversible or irreversible reaction?

H₂SO₃+ LiOH is an irreversible acid-base reaction and is always a neutralization reaction. Here chemical equilibrium of the reaction shifted right-hand side only.

H₂SO₃ + 2LiOH —–> Li₂SO₃ + 2H₂O

15. Is H₂SO₃ + LiOH displacement reaction?

H₂SO₃+ LiOH is an example double displacement reaction because in the above reaction Li⁺ is displaced by H⁺ in H₂SO₃ forming corresponding sulfate and Li⁺ cations also displaced H⁺ and formed H₂O.

Conclusion

The above reaction is an acid-base neutralization reaction. So by this reaction we can standardize the corresponding acid or base. In this reaction, the salt of lithium sulfite formed so it has industrial use.

Biswarup Chandra Dey

Hi……I am Biswarup Chandra Dey, I have completed my Master’s in Chemistry from the Central University of Punjab. My area of specialization is Inorganic Chemistry. Chemistry is not all about reading line by line and memorizing, it is a concept to understand in an easy way and here I am sharing with you the concept about chemistry which I learn because knowledge is worth to share it.