11 Iodic Acid Uses: Facts You Should Know!

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Iodic acid(HIO3) or mono iodic acid is a powerful oxyacid of iodine in which iodine is present in the +5 oxidation state. Let us discuss some important uses iodic acid.

The different uses of Iodic acid are listed below-

  • Standardization process
  • In iodate Salt production
  • Uses of iodic acid salts
  • In Chemical clock experiment
  • Periodic acid preparation
  • Laboratory uses

Standardization process:

Iodic acid is a strong acid, and used in the standardization process of bases in presence of a suitable acid-base indicator.

In iodate salt production:

Iodic acid is used to prepare the iodate salts like sodium iodate (NaIO3) and potassium iodate (KIO3) in the laboratory.

  • HIO3 + NaOH → NaIO3 + H2O
  • HIO3 + KOH → KIO3 + H2O

Use of iodic acid salts:

  • Iodic acid salts (KIO3 and NaIO3) have extensive industrial applications. Used as the source of iodine to increase the iodine content of salt in salt industries.
  • Iodic acid salts (KIO3 and NaIO3) are used in some foods and drinks as an ingredient as well as food preservatives.
  • Iodate salts are used in the iodometric titration experiment.
  • Sodium iodate strengthens doughs by oxidizing proteins, so it has got important use in the bakery and cookies industries.
  • Iodic acid salts are used as a reagent in synthesis processes, in personal care products and in many agricultural and pharmaceutical applications.

In Chemical clock experiment:

Iodic acid salts are used in very famous kinetic experiment called the Iodine Clock Experiment as a source of iodide ions. The process involves several Red-ox reactions and sodium bisulfite act as a reducing agent. When no bisulfite will be left in reaction then the free iodine forms a dark blue complex with starch.

  • IO3– + 3 HSO3–   → I– + 3HSO4– (slow, rate determining step)
  • IO−3 + 5 I− + 6 H+ → 3 I2 + 3 H2O( Iodate oxidizes I− to I2)
  • I2 + HSO3− + H2O → 2 I− + HSO4− + 2 H+ (I2 reduced back to I− by HSO3−)

Periodic acid preparation:

Iodic acid is used to prepare Periodic acid(H5IO6) in chemical industries by oxidizing the iodate in the presence of a base.

  • IO−3 + 6HO− – 2 e− → IO6−5 + 3 H2O (Electrochemically by using lead oxide as anode)
  • IO−3 + 6HO− + Cl2 → IO6−5 + 2 Cl− + 3 H2O (by using Cl2)

Laboratory uses:

  • Iodic acid when dehydrated at a temperature above 170oC, it produces Iodine Pentoxide(I2O5), the most stable oxide of iodine.
  • 2HIO3 → I2O5 + H2O
  • The reaction of iodic acid and magnesium hydroxide gives Magnesium iodate [Mg (IO3)2], a relatively insoluble tetrahydrate.
  • Mg (OH)2 + 2HIO3 → Mg (IO3)2 + H2O

Conclusion

Iodic acid primarily has a few applications, but the salts of Iodic acid like KIO3, NaIO3, Ca(IO3)2, and Ag(IO3) have numerous applications equally in laboratories as well as in different industries.