He Iodic acid Is an inorganic compound of formula HIO 3 . It is an oxido acid of iodine, which has a +5 oxidation state in this molecule.
The compound is a very strong acid and is often used to standardize solutions of weak and strong bases to prepare them for titrations.
Figure 1: Structure of iodic acid.
The acid is formed by oxidizing the diatomic iodine with nitric acid, chlorine, hydrogen peroxide Or hydrochloric acid as shown in the following reaction:
I 2 + 6H 2 O + 5Cl 2 ⇌ 2H10 3 + 10HCl
In each reaction, the diatomic iodine loses electrons and forms a complex with hydrogen and oxygen. Due to its ionic and soluble properties, the ionic acid is also a very strong acid.
Physical and chemical properties of iodic acid
Iodic acid is a white solid at room temperature (Royal Society of Chemistry, 2015).
Figure 2: Iodic acid appearance.
The iodic acid has a molecular weight of 175.91 g / mol and has a density of 4.62 g / ml. It is very soluble in water, being able to dissolve 269 grams of acid per 100 ml. Its melting point is 110 degrees Celsius, where it begins to decompose by dehydrating to iodine pentoxide.
Upon subsequent heating of the compound to a higher temperature, it is decomposed to give a mixture of iodine, oxygen and lower iodine oxides (National Center for Biotechnology Information, S.F.).
It is a relatively strong acid with an acidity of 0.75. The iodine or iodide ion is the product of this compound when it oxidizes. At very low pH and high concentration of chloride ion is reduced to iodine trichloride which is a yellow compound in solution.
Reactivity and hazards
Iodic acid is a stable compound under ordinary conditions. Being a strong acid, it is extremely dangerous in case of contact with the skin (corrosive and irritant), contact with the eyes (irritant) and in case of ingestion. In addition, it is very dangerous also in case of inhalation (IODIC ACID, S.F.).
The amount of tissue damage depends on the length of the contact. Contact with eyes may result in corneal damage or blindness. Contact with skin may cause swelling and blisters. Inhalation of dust will produce irritation of the gastrointestinal or respiratory tract, characterized by burning, sneezing and coughing.
Severe overexposure may result in lung damage, asphyxia, loss of consciousness or death. Prolonged exposure may cause skin burns and ulcerations. Overexposure by inhalation may cause respiratory irritation.
Inflammation of the eye is characterized by redness, watering and itching. Inflammation of the skin is characterized by itching, peeling, redness or, occasionally, blistering.
The substance is toxic to the kidneys, lungs and mucous membranes.
Repeated or prolonged exposure to the substance may cause damage to these organs and irritation of the eyes. Periodic exposure to the skin may result in local skin destruction, or dermatitis.
Repeated inhalation of dust may produce a varying degree of respiratory irritation or lung damage. Prolonged inhalation of dust may cause chronic respiratory irritation.
In case of contact with eyes, check for wearing contact lenses and remove them immediately. The eyes should be flushed with tap water for at least 15 minutes, keeping the eyelids open, and cold water may be used. Eye ointment should not be used.
If the chemical comes into contact with clothing, remove it as quickly as possible, protecting your own hands and body. Place the victim under a safety shower.
If the chemical builds up on the victim's exposed skin, such as hands, gently and thoroughly wash contaminated skin with running water and non-abrasive soap. If irritation persists, seek medical attention and wash contaminated clothing before reuse.
If contact with the skin is severe, it should be washed with a disinfectant soap and cover the skin contaminated with an anti-bacterial cream.
In case of inhalation, the victim should be allowed to stand in a well-ventilated area. If the inhalation is severe, evacuate the victim to a safe area as soon as possible and loosen tight clothing (shirt collar, belts, or tie).
If it is difficult for the victim to breathe, oxygen should be administered. In the extreme case of not breathing, a mouth-to-mouth resuscitation is performed. Of course, it must be taken into account that it can be dangerous for the person who provides help when the inhaled material is toxic, infectious or corrosive.
In case of ingestion, do not induce vomiting, loosen clothing and if victim is not breathing, perform mouth-to-mouth resuscitation.
In all cases seek immediate medical attention (Material Safety Data Sheet Iodic acid, 2013).
Uses and benefits for health
Iodic acid is commonly used as a standardizing agent for weak and strong base solutions. It is a strong acid that is used in analytical chemistry to perform the titrations. It is used with the methyl red or methyl orange indicators to perform the equivalence point readings in the titrations.
It is used in the salt industry to synthesize sodium or potassium iodate salt. By using this iodic acid compound in the salt preparation, the iodine content of the salt is increased (Omkar Chemicals, 2016).
This compound has long been used for organic synthesis since it has the ability to selectively oxidize organic compounds, given its action to do equivalent partial oxidation analysis, a useful technique for determining structures (Roger J. Williams, 1937).
Iodine and iodic acid are used as an efficient combination of reagents for the iodination of aryl hydroxy ketones. In the work of (Bhagwan R. Patila, 2005), a variety of ortho-hydroxy substituted aromatic carbonyl compounds were regioselectively iodinated with iodine and iodic acid in excellent yields.
References
- Bhagwan R. Patila, S. R. (2005). Iodine and iodic acid: an efficient reagent combination for iodination of aryl hydroxy ketones. Tetrahedron Letters Volume 46, Issue 42, 7179-7181. Arkat-usa.org.
- IODIC ACID. (S.F.). Retrieved from chemicalland21: chemicalland21.com.
- Material Safety Data Sheet Iodic acid. (2013, May 21). Retrieved from sciencelab: sciencelab.com.
- National Center for Biotechnology Information. (S.F.). PubChem Compound Database; CID = 24345. Retrieved from PubChem.
- Omkar Chemicals. (2016, June 11). NATURE OF IODIC ACID AND ITS USES IN VARIOUS PURPOSES. Retrieved from Omkar Chemicals Official Blog: omkarchemicals.com.
- Roger J. Williams, M.A. (1937). THE SELECTIVITY OF IODIC ACID IN THE OXIDATION OF ORGANIC COMPOUNDS. Journal of american chemical society 59 (7), 1408-1409.
- Royal Society of Chemistry. (2015). Iodic acid. Retrieved from chemspider: chemspider.com.