Chlorine Gas Formula

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Molecular Formula of Chlorine

Chlorine, abbreviated as Cl, is the second lightest halogen. This chemical element has an atomic number of 17. It takes on the appearance of pale yellow-green gas. Chlorine in liquid form can burn the skin, and chlorine in gaseous form irritates the mucous membrane. It is found between fluorine and bromine on the periodic table. 

What is the Chemical Formula for Chlorine?

\[Ne3s^{2}3p^{5}\] is its electrical configuration. There are two stable isotopes of chlorine. They are \[^{37}Cl\] and \[^{35}Cl\], respectively. The stable radioisotope of chlorine is \[^{36}Cl\]. The most common chlorine chemical is sodium chloride, while hydrogen chloride is the simplest. The molecular formula of sodium chloride is NaCl, while the molecular formula of hydrogen chloride is HCl. It has high reactivity.

Chlorine exists in the form of chloride. Do you know the chemical formula of chloride? Chloride is represented as \[Cl^{-}\] and hence \[Cl^{-}\] is chloride formula.

Now, we will discuss the chlorine formula in detail.

Chlorine Gas Formula and Structure 

Chlorine gas has the chemical structure \[Cl_{2}\] and has a molecular weight of 70 g/mol. Cl-–Cl, commonly known as the element form of chlorine, has a structure that consists of two chlorine atoms connected by a covalent connection. Both atoms have an \[sp^{3}\] orientation, which means that they have a tetrahedral structure. In the typical representations for organic compounds, their chemical structure can be expressed as follows

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The chlorine gas formula structure is shown above.


Although chlorine gas is extremely reactive, the chlorine ion is abundant in nature, particularly in the form of inorganic salts such as NaCl.

Preparation of Chlorine

The Chlor-alkali process, in which a solution of NaCl is electrolytically dissolved by the application of a current, produces hydrogen gas, chlorine gas, and sodium hydroxide. It is one technique of producing chlorine gas.

\[2NaCl + 2H_{2}O \rightarrow  Cl_{2} + H_{2} + 2NaOH\]

Because sodium chloride is taken from saltwater, lakes, or mineral sources, this procedure is inexpensive.

A second approach involves combining hydrochloric acid with manganese dioxide to produce chlorine.

Properties of Chlorine

Physical Properties:

\[Cl_{2}\] is the chlorine formula. Its colour is yellow-green, and its odour is comparable to that of household bleach. It is water-soluble and interacts with water to create hypochlorous and hydrochloric acids.

Chlorine chemical formula- \[Cl_{2}\]

Molecular weight- 70.906 g/mol

Density- 3.2 g/lt

Melting point- -101.5 °C

Boiling point- -34.038°C

Chlorine is a stifling greenish-yellow gas with a foul odour. It liquefies around 35°C and is water soluble to a degree. It’s sold as compressed liquefied gas.

Chemical Properties:

Many of the properties of chlorine gas are similar to those of elemental chlorine. It is the most basic form of the chlorine element, due to the \[Ne3s^{2}3p^{5}\] configuration of the chlorine atom, which is too unstable to survive as an isolated species. 

Applications of Chlorine Gas

  1. Because of its disinfecting characteristics, chlorine gas is employed in water treatment. It is used as a bleaching agent in the paper industry.

  2. Chlorine gas is an inorganic gas that is utilised in controlled quantities in the chemical industry. It is controversial because it has been used in chemical weapons.

  3. Because of its non-metallic behaviour, this diatomic molecule is very reactive and has a high electronegativity. It's a halogen, and the most well-known chemical is sodium chloride (NaCl). Table salt is made up of sodium chloride (NaCl). It's a common bleaching agent used to keep viruses and germs out of drinking water. It's also used in dyes, pharmaceuticals, and the automobile and agriculture industries.

Health Hazards

When vinegar is concentrated, it is extremely hazardous to one's health and can be lethal if inhaled. It irritates the eyes and causes skin discomfort. Because it is a strong oxidising agent, it can potentially cause a fire. Aquatic life is poisoned by it. When chlorine gas in high concentrations comes into contact with the skin, it causes significant irritation and tissue destruction. Burning, blistering, and prickling sensations are all possible symptoms. It produces serious burns when it comes into contact with the eyes. Because it is exceedingly poisonous, inhaling high doses of this gas produces unconsciousness.

Chlorine Blood Test

A chlorine blood test is taken to diagnose any illness that is caused by chlorine in any form. It also gives us the amount of chlorine that is present in our bodies. Chlorine is one of the electrolytes that are present in our body, they control the body fluids, acid levels, and related physiological activities. It is measured to find out if a person is suffering from kidney disease, liver failure, heart disease, and changes in blood pressure.

If you have any acid or fluid imbalance, you need to take a chlorine blood test. Apart from the chlorine content, this test also gives you a profile of other electrolytes present in your body. If the doctor asks you to take the test, sometimes you have to fast for hours before taking this test. If the results indicate high levels of chlorine, it means that the person is suffering from dehydration, kidney failure, liver diseases, acidosis, alkalosis, etc. If the results show low levels of chlorine, it suggests that the person is suffering from heart failure, lung disease, or Addison’s disease in which the adrenal glands do not secrete enough levels of hormones and it causes various symptoms ranging from dizziness, weight loss to dehydration. 

However, any conclusions can not be drawn just from the reports without proper consultation of the experts.


The second lightest halogen is chlorine, abbreviated as Cl. It takes on a pale yellow-green gas look. Chlorine burns the skin when it is liquid, and chlorine irritates the mucous membrane when it is gaseous. The chlorine gas formula is \[Cl_{2}\]. Chlorine gas is an inorganic gas that is utilised in controlled quantities in the chemical industry. It is controversial because it has been used in chemical weapons. It's a halogen, and the most well-known chemical is sodium chloride (NaCl).

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FAQs (Frequently Asked Questions)

1. Is it chlorine (Cl) or chlorine (\[Cl_{2}\])?

One molecule of chlorine gas has the formula \[Cl_{2}\]. Chlorine has only one chemical symbol: Cl. \[H_{2}\], \[N_{2}\], \[O_{2}\], and \[Cl_{2}\] are diatomic molecules that exist in gases such as hydrogen, nitrogen, oxygen, and chlorine. One molecule of gas, such as Cl–-Cl, has two atoms bonded by a covalent bond.

2. What is the formula of chloride? What is a typical level of chloride in the body?

“\[Cl_{2}\]” is the formula of chloride, it has two atoms of chlorine.Common normal range is 106 milliequivalents per litre (mEq/L) or 106 millimoles per litre (millimol/L). The normal value ranges may differ slightly between laboratories. Discuss the significance of your specific test results with your healthcare professional. Chloride levels in our body higher than these normal levels indicate dehydration, kidney issues, and acidosis (a condition in which your body has too much acid level); it can also cause alkalosis (a condition where too many bases are present in the human body). Any issues can be sorted out by taking a simple chlorine test.

3. What is the impact of chlorine on the human body?

Chlorine is a volatile gas and when it comes into contact with different parts of the human body, it causes several ill effects. Chlorine gas is heavier than the air, so it settles down due to its weight. People can easily come into contact with it, skins and eyes are the first organs to sense the irritation caused by liquid chlorine, and when we inhale chlorine in gaseous form, it causes mucous damage. Compressed chlorine gas can cause frostbite to the eyes and skin. When high levels of chlorine gas are inhaled, it causes pulmonary oedema in human beings. Chlorine combines with water to form acids when it enters the body through inhaling, ingesting, or skin contact. The acids are corrosive and cause damage to body cells when they come into touch with them.

4. What are the applications of chlorine?

Chlorine is one of the five to six chemically related elements of the periodic table that is halogens. It is a pale-yellow gas represented by the symbol “Cl” which irritates our skin when it is in a liquid state and causes suffocation to mucus when it is in the gaseous state. Following are the uses of chlorine gas:

  • It is used to counter the pungent smell produced by the dead and decaying organisms.

  • Chlorine is also used as a disinfectant to treat wounds and cuts.

  • Bacteria present in the water can be killed using chlorine and can be purified potable water.

  • Chlorine is also used to clean swimming pools and kill any bacteria that causes skin diseases. 

  • Chlorine is used as an antiseptic to treat minor cuts and wounds.

  • It is used in manufacturing drugs, plastics, and dyes. 

It is highly volatile and when it comes to direct contact with the skin, it causes dermatic issues. 

5. What are the diseases associated with chlorine gas?

Chlorine is one of the halogens that belongs to a group of elements in the periodic table that are chemically connected. It is very volatile and causes dermatic issues when it comes to direct dermatic contact. Though chlorine is used as a disinfectant and  manufactures drugs, dyes, and plastics, it also has the following disadvantages:

  • Chlorine is a volatile gas; when it is in a liquid state, it causes skin diseases and when it is in a gaseous state, it causes irritation to the mucous membrane. 

  • When human beings breathe air that has high chlorine content, they suffer from pulmonary oedema where high content of fluid gets built up in the lungs. 

  • When we come into contact with compressed chlorine, it causes frostbite of the skin and eyes.

  • Even exposure to low levels of chlorine is harmful as it irritates the eyes, nose, and ears. 

  • “Organochlorines” are compounds related to chlorine that have recently caused unknown deaths in Eluru city in Andhra Pradesh.

  • Chlorine gas is heavier than the air; hence, it settles down and people easily come into contact with it and get irritated.