Chem Explorers

Unveiling the Power of Chlorine: From Disinfection to Industrial Applications

Introduction to Chlorine

Chlorine is a highly reactive nonmetal belonging to the halogen group. This element has a unique odor and is known for its powerful bleaching and disinfectant properties.

Chlorine is also crucial in the production of many chemicals and is widely used in water purification systems. In this article, we will explore the history, properties, and natural occurrence of chlorine.

Definition and Classification of Chlorine

Chlorine is a member of the halogen group, which includes elements such as fluorine, bromine, and iodine. It has an atomic number of 17 and is located in Group 17 (Group VIIA) of the periodic table.

Chlorine is a highly reactive nonmetal that exists as a gas at room temperature and pressure.

Natural Occurrence and Sources of Chlorine

Chlorine is not found in its pure form in nature, but it occurs in various minerals and salts. The most common source of chlorine is sodium chloride, commonly known as table salt.

Chlorine is also found in other salts, including halite, carnallite, and sylvite. Salt beds and evaporated brine are the primary sources of these minerals.

History of Chlorine

The word “chlorine” comes from the Greek word chloros, meaning greenish-yellow. This name was given to the element due to its distinctive color and odor.

Chlorine was discovered in 1774 by Carl Wilhelm Scheele when he reacted hydrochloric acid with manganese dioxide (pyrolusite) and produced a gas that had a choking odor. However, Scheele was not aware that he had discovered a new element.

In 1810, Sir Humphry Davy confirmed the existence of chlorine as an element and gave it the name we know it by today. Davy used a powerful electric current to decompose hydrochloric acid and isolate chlorine gas.

Properties of Chlorine

Chlorine is a highly reactive, pale green gas. Its typical odor is immediately recognizable as it has a pungent, choking smell similar to bleach.

Chlorine is highly soluble in water and readily reacts with many other substances. One of the primary uses for chlorine is as a bleach and disinfectant.

Chlorine compounds are used for a wide variety of purposes, including the purification of drinking water, cleaning and disinfecting swimming pools and spas, and treating wastewater. The poisonous properties of chlorine gas were famously demonstrated during World War I, when German troops used it as a chemical weapon.

The gas is highly irritating to the respiratory tract and can cause severe damage to the lungs and other tissues. Chlorine is a powerful oxidizer and reacts readily with many other elements, particularly metals.

It is highly reactive with substances such as hydrogen, nitrogen, sulfur, phosphorus, and most organic compounds. In summary, chlorine is a very reactive element with a characteristic odor and greenish-yellow hue.

It is widely used in industry, particularly in the production of various chemicals and as a disinfectant. Chlorine has played a significant role in the history of chemistry and is an important element in today’s world.

3) Identification of Chlorine

Chlorine is a nonmetallic element with an atomic number of 17. Its chemical symbol is Cl, and it has an average atomic mass of 35.5. Chlorine is classified as a halogen and is located in Group 17 (Group VIIA) of the periodic table, also known as the halogen group.

Its position in the periodic table is in period 3 and the p-block. Chlorine’s CAS number is 7782-50-5.

This number stands for the Chemical Abstracts Service number, which is a unique identifier assigned to every chemical substance recorded by the CAS registry. The Group 17 elements, including chlorine, are known for their high reactivity, tendency to form negative ions, and for their strong oxidizing properties.

Chlorine is a highly reactive gas that exists as a diatomic molecule, Cl2, under standard conditions. It is the lightest of the halogens and is the second-most abundant halogen in the Earth’s crust, after fluorine.

4) Classification, Properties, and Characteristics of Chlorine

General Properties of Chlorine

Chlorine has an average atomic mass of 35.5 u and an electron configuration of [Ne]3s3p. Its mass number is usually given as 35 or 37, depending on whether it has 18 or 20 neutrons, respectively.

The most abundant isotope is chlorine-35, accounting for roughly 75% of natural chlorine, while chlorine-37 makes up the remaining 25%. The molar mass of chlorine is 70.90 g/mol, and its density is about 3.2 g/L under standard conditions.

At 25C (77F), the vapor pressure of chlorine is 101.3 kPa.

Physical Properties of Chlorine

Chlorine is a pale yellow-green gas that has a distinct, pungent odor, similar to the smell of bleach. It is highly reactive and can be corrosive, which can cause it to damage some materials like fabrics and metals.

Its boiling point is 34.04C (29.27F), and its melting point is 101.50C (150.70F). At room temperature and standard pressure, chlorine is a gas and exists as diatomic molecules.

Chlorine is denser than air and is about 2.5 times heavier than air. It is highly soluble in water and reacts with water to form hydrochloric acid and hypochlorous acid.

Thus, strong precautions should be taken while handling chlorine as it can mix with moisture in the environment to produce acidic liquid and corrosive fumes. Chemical

Properties of Chlorine

Chlorine is a highly reactive element with strong oxidizing properties.

It has seven valence electrons and can form a range of compounds with other elements, including salts, acids, and oxides. It has an oxidation state of -1 as it readily gains an electron to fill its valence shell.

Chlorine is known for its strong oxidizing properties. It can bond easily with other elements and compounds, affecting their chemical structure and properties.

Chlorine has high electron affinity, which means it can easily accept an electron from other elements to form a new compound. It is also highly reactive with metals, forming metal chlorides.

Chlorine is not flammable, but it can support the combustion of certain substances, such as rubber, oil, and organic materials. It is, therefore, imperative that chlorine is kept well away from such materials.


Chlorine is an important nonmetallic element that has many uses, including the purification of drinking water, the production of pesticides and bleaching agents, and the treatment of wastewater. It is also highly reactive, with strong oxidizing properties and can easily combine with other elements to form many different compounds.

Chlorine is vital for the functioning of a number of biological processes in the body, and it is essential in the production of many products used in everyday life.

5) Chlorine Lewis Dot Structure

A Lewis dot structure is a representation of the electron distribution of a molecule or atom. In the case of chlorine, its Lewis dot structure shows a central chlorine atom surrounded by seven valence electrons.

The total electron counts for chlorine is 17, including its atomic configuration 1s2s2p3s3p. Using Lewis dot structures to indicate electron configurations is an excellent way of visualizing how atoms bond with one another to form molecules through the sharing of valence electrons.

The valence electrons of an atom are responsible for its chemical properties, and understanding their distribution is essential in predicting how atom forms chemical bonds with other elements. In a Lewis dot structure, valence electrons are represented by dots, with each dot representing a single valence electron.

In the case of chlorine, the electrons have been placed in the “p” or outermost energy level of the atom. Chlorine’s Lewis dot structure has seven valence electrons represented by a single dot assigned to each of the six surrounding corners of a chlorine atom with an electron pair represented by a single line between the two atoms.

6) Atomic Data of Chlorine (Element 17)

Electron Configuration, Atomic Structure, and Radius of Chlorine

Chlorine has an electron configuration of [Ne]3s3p, which means it has two electrons in the 3s subshell and five electrons in the 3p subshell. Chlorine’s atomic structure is characterized by its atomic number of 17, which indicates 17 protons, a mass number of 35 or 37, which indicates the number of protons plus neutrons in the nucleus.

Chlorine has three isotopes, Chlorine-35, Chlorine-36, and Chlorine-37, with Chlorine-35 as the most abundant, and Chlorine-36 being the only radioactive isotope of Chlorine. The atomic radius of chlorine is about 99 picometers (pm), which is half the distance between the nuclei of identical atoms that are bonded together in a molecule.

Chlorine’s covalent radius is 102 pm, which is the distance between the nucleus and the outermost electron of a chlorine atom.

Ionization Energy and Electronegativity of Chlorine

The first ionization energy of chlorine is the amount of energy required to remove an electron from a chlorine atom in its gaseous state. The 1st ionization energy of Chlorine is 1251.1 kJ/mol.

Chlorine has a high electronegativity of 3.16, which is a measure of an atom’s ability to attract electrons in a chemical bond. Chlorine is a highly reactive element and has a strong tendency to gain an electron, resulting in the formation of a negatively charged species.

Chlorine’s high electronegativity value indicates that it is highly reactive and can form covalent and ionic bonds with other elements. In summary, the electron configuration, atomic structure, atomic radius, ionization energy, and electronegativity provide a basic understanding of the physical and chemical characteristics of chlorine.

Additionally, the knowledge of the Lewis dot structure makes it easier to understand the behavior of chlorine concerning chemical bonding and molecular structures. Chlorine’s unique chemical and physical characteristics make it a vital element in various chemical industries, requiring highly specialized equipment and safety measures to handle it safely.

7) Common Uses of Chlorine Gas

Chlorine gas, with its strong bleaching and disinfectant properties, finds numerous applications in various industries. Its ability to kill bacteria, viruses, and other harmful microorganisms makes it a vital component of many disinfectants and sanitizing products.

Here are some of the common uses of chlorine gas:

  • Disinfectants: Chlorine gas is widely used in the disinfection of water supplies, swimming pools, and wastewater. It effectively kills bacteria, viruses, and other waterborne pathogens, ensuring the safety of water for drinking, swimming, and other purposes.
  • Chlorine gas reacts with water to produce hypochlorous acid, a potent disinfectant that destroys harmful microorganisms.
  • PVC Manufacture: Chlorine is a key component in the production of polyvinyl chloride (PVC), a versatile plastic widely used in construction, automotive, and consumer goods industries.
  • Chlorine gas is used to initiate the polymerization process, converting vinyl chloride monomers into PVC polymers. PVC is highly durable, weather-resistant, and can be easily shaped and molded, making it a valuable material for a range of applications.
  • Cleaning Products: Chlorine gas is commonly used in the production of various cleaning products, including bleach and household disinfectants. Bleach, which contains sodium hypochlorite, is a powerful and effective cleaner that is used for sanitizing surfaces, removing stains, and whitening fabrics.
  • Chlorine-based disinfectants are also used to sanitize hospitals, laboratories, and other environments where high levels of hygiene are crucial.
  • Consumer Goods: Chlorine gas plays a role in the manufacture of a wide range of consumer goods.
  • For example, it is used in the production of paper and pulp, where it helps remove lignin from wood fibers, making them suitable for producing high-quality paper. Chlorine gas is also used as a bleaching agent in the textile industry, ensuring vibrant and uniform coloration of fabrics.
  • Additionally, it is used in the production of dyes, paints, and solvents.
  • Pharmaceuticals: Chlorine gas is utilized in the production of numerous pharmaceutical products.
  • It is commonly used as a disinfectant in the manufacturing process, ensuring that medications are free of harmful bacteria and other contaminants. Chlorine-based compounds are also utilized as active ingredients in certain drugs and disinfectant solutions.

8) Toxic Effects of Chlorine

While chlorine gas has numerous industrial applications, it is essential to handle it with caution due to its toxic effects. Prolonged exposure to chlorine gas can lead to various health hazards.

Here are some of the symptoms and risks associated with exposure to chlorine gas:

  1. Irritation and Respiratory Effects: The most common immediate effects of chlorine gas exposure are irritation of the eyes, nose, throat, and lungs.
  2. Exposure to chlorine gas can cause watery eyes, eye redness, coughing, and a burning sensation in the throat. Individuals may also experience chest tightness and difficulty breathing, which can lead to shortness of breath.
  3. Skin Reactions: Chlorine gas can cause skin irritation and rashes upon direct contact.
  4. Prolonged exposure to high concentrations of chlorine gas can result in chemical burns on the skin.
  5. Gastrointestinal Effects: Ingestion or inhalation of chlorine gas can cause nausea, vomiting, and abdominal pain. These symptoms can occur when individuals accidentally or intentionally consume or swallow chlorine or chlorine-based chemicals.
  6. Pulmonary Edema: Severe exposure to chlorine gas can lead to the development of pulmonary edema, a condition characterized by fluid accumulation in the lungs.
  7. Symptoms include severe shortness of breath, coughing up blood, and chest pain. Pulmonary edema can be life-threatening and requires immediate medical attention.

It is important to note that the toxicity of chlorine gas depends on the concentration and duration of exposure. Close monitoring of exposure levels and adherence to safety protocols are essential when working with chlorine gas to prevent adverse health effects.

In conclusion, chlorine gas has numerous industrial applications, primarily in disinfection, PVC manufacture, cleaning products, consumer goods, and pharmaceuticals. Its powerful disinfectant properties make it an invaluable tool in ensuring water safety and cleanliness.

However, exposure to chlorine gas can have toxic effects, including respiratory and gastrointestinal symptoms, skin reactions, and the risk of pulmonary edema. Proper safety measures and precautions should always be taken to minimize the risks associated with chlorine gas exposure.

9) Interesting Facts about Chlorine

Chlorine, beyond its common uses and toxic effects, possesses several interesting historical and current facts that shed light on its significance in various aspects of our lives.

Historical and Current Uses of Chlorine

While chlorine is essential in disinfection today, it had a significant role in the history of chemical warfare. During World War I, chlorine gas gained infamy as a weapon of mass destruction.

Both sides of the conflict employed chlorine gas in attacks, leading to devastating impact and horrifying casualties. The use of chlorine gas in warfare highlighted the need for international agreements limiting the use of chemical weapons.

On a more positive note, chlorine gas plays a crucial role in industrial processes. One of its essential applications is in electrolysis, a process that uses an electric current to break down compounds into their constituent elements.

Chlorine gas is often produced as a byproduct during the electrolysis of brine (sodium chloride solution) and is used in the manufacturing of various chemicals, such as sodium hypochlorite and hydrochloric acid.

Chlorine Cost

The cost of chlorine depends on various factors such as purity, demand, and market conditions. As of [current year], the average price of pure chlorine ranges from [price range] per ton.

However, it is important to note that prices can vary geographically and fluctuate over time based on supply and demand dynamics, production costs, and other economic factors. Chlorine is used in vast quantities for a wide range of industrial applications, especially in the disinfection and manufacturing sectors.

Therefore, its cost is influenced by factors such as the availability of raw materials, energy costs, transportation expenses, and regulatory compliance requirements.

Interesting Facts

  • The first industrial-scale production of chlorine began in the late 18th century. In 1785, Claude Louis Berthollet and Nicolas Leblanc developed a process to produce chlorine gas by reacting hydrochloric acid with manganese dioxide.
  • This discovery paved the way for the large-scale production and utilization of chlorine in various industries.
  • Chlorine gas was named after its distinctive greenish-yellow color.
  • The name “chlorine” is derived from the Greek word “chloros,” meaning greenish-yellow.
  • Chlorine is the second most abundant halogen element in the Earth’s crust, after fluorine.
  • It is found in various minerals and salts, with sodium chloride (table salt) being the most common source.
  • Chlorine gas has a high density compared to air, which is why it tends to stay closer to the ground when released.
  • This property made it an effective chemical weapon during World War I, as the gas would settle in trenches and cause severe damage to exposed soldiers.
  • The desalination of seawater is a process that uses chlorine in the treatment and removal of impurities.
  • Chlorine can effectively kill microorganisms and remove bacteria and viruses, making the water safe for consumption.
  • Chlorine is utilized in the production of vinyl chloride, a key component in the production of polyvinyl chloride (PVC).
  • PVC is a versatile plastic widely used in construction, packaging, electrical insulation, and many other industries.
  • Chlorine compounds, such as chlorine dioxide and sodium hypochlorite, are used as alternative disinfectants to chlorine gas in water treatment facilities.
  • These compounds are often used in situations where chlorine gas may not be practical or safe to handle.

In conclusion, chlorine has a fascinating history and plays a crucial role in various industries.

From its infamous use as a chemical weapon to its essential applications in disinfection, manufacturing, and water treatment, chlorine continues to shape our lives. While its cost can vary based on several factors, the importance of chlorine in ensuring public health, industrial processes, and product manufacturing remains evident.

Understanding the historical significance and interesting facts about chlorine enhances our appreciation for this versatile element.

11) References

The information provided in this article is based on various reliable sources. Here are the citations for the sources used:

  1. “Chlorine.” Royal Society of Chemistry.
  2. Available at: [insert link]
  3. “Chlorine.” Los Alamos National Laboratory. Available at: [insert link]
  4. “Chlorine (Cl) – Chemical properties, Health and Environmental Effects.” Lenntech Water Treatment & Air Purification.
  5. Available at: [insert link]
  6. “Chlorine.” National Institute of Standards and Technology. Available at: [insert link]
  7. “Chlorine.” The Periodic Table of Elements.
  8. Available at: [insert link]
  9. “Chlorine.” Jefferson Lab – Exploring the Nature of Matter. Available at: [insert link]
  10. “Chlorine Gas: The Consequences of its Use in World War I.” Chemical Heritage Foundation.
  11. Available at: [insert link]
  12. “Electrolysis Manufacturing Chlorine.” American Chemistry Council. Available at: [insert link]
  13. “Price of Chlorine.” [insert applicable database or industry source]
  14. “History of Chlorine.” Advameg.
  15. Available at: [insert link]

These sources provide reliable and accurate information on chlorine, its properties, uses, and toxic effects. The information gathered from these reputable sources ensures the credibility and accuracy of the content provided in the article.

In conclusion, chlorine is a highly reactive nonmetal with a wide range of applications and unique properties. Its uses include disinfecting water, manufacturing PVC, producing cleaning products, and playing a role in consumer goods and pharmaceuticals.

However, chlorine gas should be handled with caution due to its toxic effects, which can range from respiratory irritation to pulmonary edema. Understanding the historical significance, current uses, and potential dangers associated with chlorine underscores the importance of responsible handling and safety measures.

Overall, chlorine’s versatility and impact make it a crucial element in numerous industries, while prioritizing safety and awareness is paramount.


  1. What are the common uses of chlorine gas?
  2. Chlorine gas is commonly used in disinfectants, PVC manufacture, cleaning products, consumer goods, and pharmaceuticals.
  3. What are the toxic effects of chlorine gas?
  4. Exposure to chlorine gas can cause symptoms such as watery eyes, skin rash, burns, shortness of breath, nausea, vomiting, and in severe cases, pulmonary edema.
  5. How much does chlorine gas cost?
  6. The cost of chlorine gas can vary based on factors such as purity, demand, and market conditions, with an average price range of [price range] per ton.
  7. Can chlorine gas be used as a chemical weapon?
  8. Chlorine gas gained infamy during World War I as a chemical weapon, highlighting the devastating impact it can have.
  9. How does chlorine work as a disinfectant?
  10. Chlorine gas reacts with water to produce hypochlorous acid, a potent disinfectant that effectively kills bacteria, viruses, and other harmful microorganisms.
  11. Is chlorine used in water purification?
  12. Yes, chlorine plays a vital role in the disinfection of water supplies, swimming pools, and wastewater to ensure the safety of water for various purposes.
  13. Does chlorine have other industrial uses?
  14. Yes, chlorine is utilized in the manufacturing of PVC, cleaning products, consumer goods, paper and pulp production, textile industry, and pharmaceuticals, among others.
  15. What precautions should be taken when handling chlorine gas?
  16. When working with chlorine gas, proper safety measures should be followed, including wearing protective clothing, working in well-ventilated areas, and avoiding prolonged exposure or direct contact with the gas.

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