13 Facts on HCl + NaClO2: What, How To Balance & FAQs

Sodium chlorite is formed by the reaction of chlorine dioxide and sodium hydroxide. Let us focus on the reaction of hydrochloric acid and sodium chlorite in this article.

HCl is strong acid as it shows complete dissociation. It appears as a colourless liquid. It has a pungent odour. NaClO2 appears as a white or light yellow-green solid. The molecular weight of NaClO2 is 90.44. It is soluble in water, and solubility increase with the increase in temperature.

In the following editorial, we will discuss various facts about HCl and NaClO2 reactions.

What is the product of HCL and NAClO2?

The reaction between HCl and NaClO2 has the product, sodium chloride, chlorine dioxide and water molecule.

 HCl+ NaClO2ClO2 +NaCl + H2O

What type of reaction is HCL + NACLO2?

The reaction between HCl and NaClO2 is an oxidation and reduction reaction.

How to balance HCL + NACLO2

HCl + NaClO2 reaction is balanced using the following steps.

  • To balance the reaction, first, we have to count the number of atoms on the reactant side and the number of atoms on the product side.
  • In the next step, if the number of atoms on both sides of the reaction is not equal, we have to equalize that.
  • Here reaction is HCL +NAClO2 ⟶ClO2 +NaCl + H2O
  • In HCl + NaClO2 reaction, two chloride atoms, one hydrogen atom, one sodium atom and two oxygen present on the reactant side, whereas two chloride atoms, one sodium atom, two hydrogen atoms and three oxygen atoms are present on the product side.
  • Thus on both the reactant and product side number of atoms are unequal. So we have to equalize both sides.
  • HCl + NaClO2 reaction can be balanced using the algebraic method as below.

        4HCl + 5NaClO2 ⟶ 4ClO2 +5NaCl +2H2O.

AtomNumber of atom on Reactant sideNumber of atom on Product side
Table showing number of atoms on reactant and product side

HCL + NACLO2 net ionic equation

The reaction between HCl and NaClO2 has the net ionic equation,

4H+(aq) + 4Cl(aq) + 5Na+(aq) +5ClO2(aq) ⟶4ClO2(g) +5Na+ (aq) +5Cl(aq) +2H2O(l)

4H+(aq) +ClO2 (aq) 2H2O(l) + Cl(aq)

HCL + NACLO2 conjugate pairs 

The reaction between HCl and NaClO2 has the conjugate pairs,

  • Conjugate acid – ClO2
  • Conjugate base  – NaCl                               

HCL and NACLO2 intermolecular forces

The reaction between HCl and NaClO2 has following intermolecular forces.

  • There is a weak dipole-dipole force between the HCl molecule.
  • A polar covalent force is present between Cl and H+ ion.

HCL + NACLO2 reaction enthalpy

The reaction between HCl + NaClO2 has reaction enthalpy 14.7 KJmol-1.

Is HCL + NACLO2 a buffer solution

HCl + NaClO2 is not a buffer solution as HCl is a strong acid.

Is HCL + NACLO2 a complete reaction

HCl + NaClO2 reaction is a complete reaction as ClO2 evolved as gas, and NaCl and water formed in this reaction as a product.

Is HCL + NACLO2 an exothermic or endothermic reaction

HCl + NaClO2 reaction is an endothermic reaction as this reaction has an enthalpy value positive which is noted at 14.7 KJmol-1.

Is HCL + NACLO2 a redox reaction?

HCl + NaClO2 reaction is a redox reaction. NaClO2 act as both a reducing and oxidizing agent.

4HCl-1(aq) + 5NaClIIIO2 (aq) ⟶ 4ClIVO2 ( g) + 5NaCl-1(aq) +2H2O(l).

HCl + NaClO2 is oxidation-reduction reaction as shown below.

ClIII + 4e–  Cl


4ClIII   –  4e- 4ClIV


Is HCL + NACLO2 a precipitation reaction

HCl + NaClO2 reaction is not a precipitation reaction as NaCl formed in HCl + NaClO2 reaction is soluble in water and no precipitate is formed.

Is HCL + NACLO2 reversible or irreversible reaction

HCl + NaClO2 reaction is an irreversible reaction as the ClO2 product is evolved as a gas.

Is HCL + NACLO2 displacement reaction

HCl + NaClO2 reaction is a single displacement reaction. Na from NaClO2 displaces hydrogen from HCl and forms NaCl.


This article has mentioned the reaction between hydrochloric acid and sodium chlorite. Sodium chlorite is used as a disinfectant in the water purification process. It is also used in the paper industry. Hydrochloric acid is also used in wastewater treatment.

Scroll to Top