Acids, Bases and Salts

Hydrochloric Acid

Hydrochloric acid is a strong corrosive acid. Its chemical formula is HCl. The other name for hydrochloric acid is hydrogen chloride or Muriatic acid. Hydrochloric acid is an inorganic chemical. HCl Forms when hydrogen chloride dissolves in water. Hydrochloric acid is a simple diatomic molecule, the chlorine atom and hydrogen connect over a single covalent bond. The bond that exists between them is polar because the chlorine atom is more electronegative when we compare it with a hydrogen atom.

Hydrochloric acid is strongly acidic, it is vicious as well as colourless. HCl has a corrosive nature and a distinctively pungent smell. It is useful as a laboratory reagent and in the industry. Hydrochloric acid is useful in the production of gelatin and the processing of leather. The molarity or concentration of HCl determines the physical properties, density, boiling point, melting point, PH.

Hydrochloric Acid

                                                                                           Hydrochloric Acid

Properties of Hydrochloric Acid

The molecular weight or molar mass of hydrochloric acid is 36.458  \(\frac{g}{mol}\). It appears as a transparent liquid Who is the boiling point and melting point depend on the concentration. Hydrogen chloride is a colourless gas that is highly odorous. Gaseous hydrogen chloride will respond to the chloride which forms by active metals and their hydroxide, carbonate, and oxides. In the presence of humidity, these reactions occur readily. Hydrogen chloride is unreactive as well as is completely dry.

Hydrochloric acid reactions consist of common strong acids, for example, hydrogen gas is displaced in metal reactions, reactions in which hydroxide and metal oxides become neutral with the formation of metal chloride and water, reactions consisting of weak acid salts in which the displacement of heavy acid takes place. In the presence of glass hydrochloric acid is non-corrosive. Hydrochloric acid is very corrosive and attacks metals like platinum, gold, silver, mercury, tantalum, etc. It can release only one proton as it is monoprotic.

It can completely disassociate to form hydrogen and chloride ion in water.

Uses of hydrochloric acid

1.Purification of table salt and pH Control. 

This acid purifies table salts. It is also useful in the regulation of acidity of solutions and further, it is also useful to control the pH of pharmaceutical products, water, and foods.

2. For the production of oil.

Hydrochloric acid is put into a rock where the reaction of the rock forms large-pore structures. This has significant assistance in oil production.

3. Cleaning agent.

Because of the highly corrosive nature of hydrophilic acid, it is useful as a chemical that helps to remove stains or rust from metals like copper and iron. It is useful in its diluted form. It is in use for cleaning tiles in bathrooms and kitchens and it is also useful as a disinfecting agent. In the textile industry, HCl is useful for bleaching clothes and processing in the leather tanning industry. It can also neutralize swimming pools if the pH level is high.

4. Pickling of steel.

It is a process in which dilute hydrochloric acid is in use for the removal of rust or iron oxide from steel or iron before its processing into wire production, sheet and strip coating and tin mill products.

5. Production of Organic compounds.

HCl is useful in the production of Organic compounds like vinyl chloride and dichloromethane which are useful to produce PVC. It also produces a variety of organic compounds like ascorbic acid and pharmaceutical products.

6. Production of inorganic compounds.

HCl is useful in the preparation of compounds that are useful as water treatment chemicals. For example, polyaluminium chloride(PAC), ferric acid, aluminium carbohydrate are useful in the treatment of water. It is also useful in the regeneration of ion-exchange resins and especially to rains the cations from the resins.

7. Gastric Acid.

Hydrochloric acid is a vital part of gastric juice in the body which helps in digestion. Inactive pepsinogen converts into active pepsin by hydrochloric acid in the stomach which helps digestion by breaking the bonds linking amino acids. This process is Proteolysis.

Hazards of Hydrochloric Acid

Hydrochloric acid must be handled with care as it is a hazardous liquid. The acid is corrosive and concentrates forms release acidic mists that are dangerous. If we inhale a small amount of hydrochloric acid, it will result in the nose, Eye, Respiratory Tract irritation, and inflammation in humans, there may be damage to mucus membranes, stomach as a result of oral exposure. Whereas, continuous exposure can lead to chronic bronchitis, gastritis, etc. Hence the use of personal protective equipment is essential.

Skin contact- if HCl comes in contact with skin, we must flush immediately with water for at least 15 minutes and remove the contaminated clothing. If it is a case of serious skin contact, we must use water, antibacterial cream, and disinfectant soap and furthermore seek immediate medical attention.

Ingestion- if it is swallowed we must not induce vomiting and immediate medical attention is necessary.

Eye contact- we must immediately flush with plenty of water for a minimum of 15 minutes and move forward for immediate medical attention.

Inhalation- if we inhale hydrochloric acid vapours then look for fresh air and medical attention immediately.

Handle Hydrochloric Acid Safely

 Safety is necessary when we handle dangerous chemicals like hydrochloric acid. We should wear the following protective equipment while using hydrochloric acid of any concentration:

  1. Vapour respirator
  2. Face shield
  3. Full suit
  4. Rubber gloves
  5. Boots

We should have access to an eye flush station in case of accidental exposure in the workplace. While using hydrochloric acid in households, we must follow the label directions and safety instructions closely. We must usually first dilute the cleaner to reduce its concentration.  Hydrochloric acid must be in a cool, dry and area with good ventilation away from moisture. Hydrochloric acid must be away from oxidizing agents, metals, and organic materials. The container must be tight and we must store it in a safe place.

Preparation of Hydrochloric Acid

 Hydrochloric acid preparation takes place by dissolving hydrochloride and water. The water molecules take the hydrogen atom in HCl and put it away from the chlorine atom when hydrogen chloride gas enters the water. This is known as the dissolution process which forms hydrochloric acid. Hydrogen chloride is also made as by-products of industrial-scale production of other chemicals. By the combustion of hydrogen and chlorine, its preparation takes place industrially. But because of reparation, a high concentration of HCl it is difficult to prepare. HCl can be obtained by the synthetic method on the basis of a direct combination of hydrogen with chlorine, in large quantities commercially.

FAQs about Hydrochloric Acid                

Q.1.What is the Difference between hydrogen chloride and hydrochloric acid? 

Answer: They have the same formula, but the difference is in the physical states that they exist in. Hydrogen chloride exists in a gaseous state on the other hand hydrogen chloride exists in aqua solution.

Q.2. Can we say that hydrochloric acid is a compound?

Answer: We can say that hydrochloric acid is a gas solution of water as it is a mixture of hydrogen and chlorine, it is a gas at atmospheric temperature and pressure.

Q.3. What is the other name of hydrochloric acid? 

Answer:  It is a strong chorus of acid which is widely in use as a reagent in the laboratory. It forms by dissolving water chloride from hydrogen. Gastric acid is the acid component of gastric juices.  

Q.4. What are the uses of Hydrochloric acid? 

Answer: It is useful in the production of glucose and corn sugar from starch. It is in use in the refining of cane sugar and making glue and gelatin. It is also useful in the manufacturing of synthetic rubber and plastics and in the purification of common salt. In the manufacture of aqua Regia to dissolve noble metals such as gold and platinum.

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