The chloric acid is an inorganic compound of formula HClO 3, comprises a oxyacid acid where chlorine is +5 oxidation state with a structure analogous to the bromic acid or iodic acid. It is a strong acid capable of donating hydrogen to a Bronsted acceptor or base.
Acid was first discovered in the 17th century, by Johann Rudolf Glauber of Karlstadt am Main, Germany, in which he used sodium chloride and sulfuric acid for the preparation of sodium sulfate in the Mannheim process, releasing chloride gas from hydrogen, harmful to humans.
The compound is obtained with barium chlorate (barite chlorate) with sulfuric acid to produce barium sulfate (Jacob Green, 1829) insoluble in water according to the following reaction:
Ba (ClO 3) 2 + H 2 SO 4 → 2HClO 3 + BaSO 4
Another method of obtaining is by heating hypochlorous acid to obtain chloric acid and hydrogen chloride according to the reaction:
3HClO → HClO 3 + 2HCl
Chloric acid (HClO3) is a powerful oxidant since it is capable of being reduced to oxidation states +3, +1 and -1. It is used for the manufacture of chlorate salts.
It decomposes in concentrations greater than 30%. It also decomposes when heated, for this reason, it must be kept cold all the time and all glass jars used for handling must be previously refrigerated.
Physical and chemical properties
Chloric acid exists only in solution. It is a colorless liquid without a characteristic aroma (National Center for Biotechnology Information, 2017), its appearance is shown in figure 2.
Figure 2: appearance of chloric acid.
The compound has a molecular weight of 84.459 g / mol and a density of 1 g / ml at about 25 ° C. It has a boiling point greater than 100 ° C (CHLORIC ACID, SF) and a solubility in water of 40 g per 100 ml of this solvent at 25 ° C (Royal Society of Chemistry, 2015).
Chloric acid will accelerate the burning of combustible materials and can ignite most on contact. The compound is corrosive to metals and fabrics.
Self-reactive
- Chloric acid concentrations above 40% decompose.
- Antimony sulfide and concentrated solutions of chloric acid react with incandescence.
- Arsenic sulfide and concentrated chloric acid solutions react with incandescence.
- Reacts vigorously and even explodes with other metallic sulphides, that is, copper sulphide.
- In contact with oxidizable materials, including ammonia, reactions can be extremely violent.
- The filter paper lights up after immersing it in hydrochloric acid.
- The explosions have been registered by mixtures of chloric acid solution with metals such as: antimony, bismuth and iron. This is due to the formation of explosive compounds including hydrogen (CHLORIC ACID, 2016).
Reactivity and hazards
Chloric acid is an unstable compound. Being a strong acid, it is extremely dangerous in case of contact with the skin (it is corrosive and irritant), in contact with the eyes (irritant) and in case of ingestion. Also very dangerous in case of inhalation.
Severe overexposure can cause lung damage, suffocation, loss of consciousness, or death. Prolonged exposure can cause skin burns and ulcerations.
Inhalation overexposure 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, and occasionally blistering.
The substance is toxic to the kidneys, lungs and mucous membranes. Repeated or prolonged exposure to the substance can damage these organs.
In case of contact with the eyes, check if you are wearing contact lenses and remove them immediately. Eyes should be flushed with running water for at least 15 minutes, keeping the eyelids open. Cold water can 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 accumulates on the victim's exposed skin, such as hands, the contaminated skin is gently and carefully washed with running water and non-abrasive soap.
You can also neutralize the acid with dilute sodium hydroxide or with a weak base such as baking soda. If irritation persists, seek medical attention. Wash the contaminated clothing before using it again.
If the contact with the skin is severe, it should be washed with a disinfectant soap and cover the contaminated skin with an antibacterial cream.
In case of inhalation, the victim should be allowed to rest in a well-ventilated area. If inhalation is severe, the victim should be evacuated to a safe area as soon as possible.
Loosen tight clothing such as a collar, belt, or tie. If it is difficult for the victim to breathe, oxygen should be administered. If the victim is not breathing, mouth-to-mouth resuscitation is performed.
Always taking into account that it can be dangerous for the person providing aid to give mouth-to-mouth resuscitation, when the inhaled material is toxic, infectious or corrosive.
In case of ingestion, do not induce vomiting. Loosen tight clothing such as shirt collars, belts, or ties. If the victim is not breathing, perform mouth-to-mouth resuscitation. In all cases, immediate medical attention should be sought.
Applications
Chloric acid is used mainly for the formation of chlorate salts such as: sodium, calcium, magnesium, strontium, lead, copper and silver chlorate as well as protochlor and mercury perchlorate are prepared using chloric acid as a reagent.
Stable precursor of chlorine dioxide, it is used in the electrochemical production of high purity ammonium perchlorate (Dotson, 1993).
The main production of chloric acid started during the Industrial Revolution in Europe and was used to make vinyl chloride for PVC pipes.
Another use for acid is numerous smaller-scale applications, including household cleaning, production of gelatin and other food additives, descaling, and leather processing (chloric acid, SF).
References
- CHLORIC ACID. (2016). Recovered from cameochemicals: cameochemicals.noaa.gov.
- chloric acid. (SF). Recovered from weebly:
- CHLORIC ACID. (SF). Recovered from chemicalbook: chemicalbook.com.
- Dotson, R. (1993). A novel electrochemical process for the production of ammonium perchlorate. Journal of Applied Electrochemistry Volume 23, Issue 9,, 897–904. link.springer.com.
- EMBL-EBI. (2014, July 28). chloric acid. Recovered from ebi.ac.uk: ebi.ac.uk.
- Jacob Green, ET (1829). A text book of chemical philosophy. Philadelphia: Russell & Martien.
- National Center for Biotechnology Information.. (2017, April 15). PubChem Compound Database; CID = 19654. Recovered from pubchem:.pubchem.ncbi.nlm.nih.gov.
- Royal Society of Chemistry. (2015). CHLORIC ACID. Recovered from chemspider: chemspider.com.