15 Facts on H2SO3 + Mn(OH)2: What, How To Balance & FAQs

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The purpose of a chemical reaction is to monitor the changes in the system. Let us see how this reaction occurs in terms of changes.

Manganese is a transition element. So, its hydroxide should show properties quite similar to other transition metal hydroxides. Mn(OH)2 is a white solid, partly insoluble in water. Sulphurous acid, the solution form of sulphur dioxide, is a strong acid with pH of 5.1 and acts as reducing agents and preservatives.

In this article, we will go through the reaction of acid and hydroxide, with their properties like intermolecular forces and reaction enthalpy.

What is the product of H2SO3 and Mn(OH)2?

H2SO3 and Mn(OH)2 are reacted to form manganese sulphite and water molecules respectively. The reaction occurs as:

  • H2SO3 + Mn(OH)2 → MnSO3 + 2H2O

What type of reaction is H2SO3 + Mn(OH)2?

The reaction of H2SO3 and Mn(OH)2 is a neutralisation reaction as an acidic and basic compound gives salt and water respectively.

How to balance H2SO3 and Mn(OH)2?

The rules of equating H2SO3 and Mn(OH)2 reaction are as follows:

  • H2SO3 + Mn(OH)2→ MnSO3 + H2O
  • As both ways must be equal in atoms, multiply H2O with 2 to equal with the H2 atoms of the acid. The stoichiometry is constant.
  • H2SO3 + Mn(OH)2→ Al2(SO3)3 + 2H2O

H2SO3 + Mn(OH)2 Titration

Mn(OH)2 is estimated by a process called thermometric titration. The steps for this titration are:

Apparatus

  • Graduated burette
  • Conical flask
  • Volumetric flask
  • Burette stand

Titre and Titrant

  • H2SO3 is known as the titrant, which is used to measure the analyte.
  • Mn(OH)2 is the titre, whose concentration will be determined.

Indicator

Thermometric titration does not need a colour-changing indicator as changes of enthalpy is the major factor.

Procedure 

  • In a conical flask, weighed sodium tartrate and samples of Manganese oxide are dissolved well in water.
  • Aqueous solution of H2SO4 is added as contents in the burette.
  • Under the conical flask, the conical flask contents are kept and the titration is continued.
  • A few drops of KF are included the contents of the flask and the temperature is noticed.
  • As the equivalence point of the titration comes, equal moles of the reactants have reacted and we see a noticeable change in the temperature of the solution.
  • The volume of the sample is measured according to the titration.

H2SO3 and Mn(OH)2 Net Ionic Equation

H2SO3 + Mn(OH)2 gives the following net ionic equation:

  • 2H+(aq) +SO32-(aq) + Mn2+(aq) + 2OH–(aq) → Mn2+(aq) +SO32(aq) + 2H+(aq) + 2OH–(aq)
  • In H2SO3 hydrogen and sulphite ions are formed as ionic entities.
  • Mn(OH)2 gets dissociated into two Manganese ions and three hydroxide ions.
  • MnSO3 gets dissociated into two Manganese ions of +2 oxidation state and sulphite ions.
  • Water gets dissociated to each two units of hydrogen and hydroxyl ions.

H2SO3 and Mn(OH)2 Conjugate Pairs

H2SO3 and Mn(OH)2  reaction has the following conjugate pairs, which differs by one proton:

  • The conjugate base of H2SO3 = HSO3–
  • The conjugate base of H2O= OH–

H2SO3 and Mn(OH)2 Intermolecular Forces

H2SO3 and Mn(OH)2  reaction has the following intermolecular forces,

  • H2SO3 is made up of acidic protons that causes hydrogen bonding with electronegative elements.
  • Mn(OH)2  generally forms a orthorhombic crystal structure with formula units of 4.
  • Mn(OH)2  is not polar but dispersion forces and Van de Waals’ forces are both existent.
  • Mn(OH)­2 is attracted to oxygen atoms which oxidise it to Mn3+ ions and the oxide turns brownish in colour.
ElementVan der Waals’ Radius(Å)
Hydrogen1.20
Manganese1.97
Sulphur1.80
Radius Chart

H2SO3 and Mn(OH)2 Reaction Enthalpy

H2SO3 and Mn(OH)2  reaction enthalpy data is around -520.7 kJ/mol. The enthalpy information is as follows:

  • Enthalpy of Formation of Mn(OH)2 = -695.4 kJ/mol
  • Enthalpy of Formation of H2SO3 = -655.5 kJ/mol
  • Enthalpy of Formation of MnSO3 = -1300 kJ/mol
  • Enthalpy of Formation of H2O = -285.8 kJ/mol
  • Enthalpy of Reaction = (-1300-(285.8 x 2)) – (-(655.5) – 695.4) kJ/mol

Is H2SO3 and Mn(OH)2 a Buffer Solution?

H2SO3 + Mn(OH)2 is not a strong buffer solution because sulphurous acid is so strong an acid that it can never be a part of buffer . So, it cannot regulate the pH of the solution.

Is H2SO3 and Mn(OH)2 a Complete Reaction?

H2SO4 and CH3OH reaction is called as complete reaction because products are completely formed at equilibrium.

Is H2SO3 and Mn(OH)2 an Exothermic Reaction?

The H2SO3 and Mn(OH)2 reaction is exothermic in nature. H2SO3 and Mn(OH)2 reaction breaks bonds that creates a lot of heat.

Is H2SO3 and Mn(OH)2 a Redox Reaction?

H2SO3 and Mn(OH)2 reaction is not a redox reaction because the atoms have not changed in oxidation states.

Is H2SO3 and Mn(OH)2 a Precipitation Reaction?

H2SO3 + Mn(OH)2 is not a precipitation reaction as products do not exist in the solid phase but in solution form.

Is H2SO3 and Mn(OH)2 a Reversible Reaction?

H2SO3 and Mn(OH)2 reaction is reversible beacuse it is an acid-base reaction where the products can go backward to form the reactants if conditions are not maintained.

Is H2SO3 and Mn(OH)2 a Displacement Reaction?

H2SO3 and Mn(OH)2 reaction is a double displacement reaction as both sets of ions get replaced in the product side.

  • Mn2+ ions displace H+ ions in the acid and form an acidic salt MnSO3.
  • The hydrogen ions combine with the hydroxyl ions to produce water molecules.

Conclusion

Mn(OH)2 is a relatively strong base that has a melting point of 140ºC. The equilibrium constant shows it has fair solubility in acid too. The acid and base reaction is a prime example of temperature regulated titration.