Careers360 Logo
Benzene Hexachloride - Uses, Properties, Structure, Preparation, FAQs

Benzene Hexachloride - Uses, Properties, Structure, Preparation, FAQs

Edited By Team Careers360 | Updated on Jul 02, 2025 05:06 PM IST

Benzene hexachloride is an organic compound which is an isomer of hexachlorocyclohexane with the chemical formula C6H6Cl6. This compound is also given the name lindane or hexachloride. It is a solid that is colorless and with an odor of slightly musty. This compound is also an organochlorine compound that has a wide application in the agricultural field and pharmaceutical industry.

This compound is also given the notation BHC for simplicity. Normally benzene compounds do not undergo addition reactions fast so the reaction required for the preparation of benzene hexachloride needs some extra outside stimulant which is light-induced. And thereby the addition of chlorine to benzene gives many isomers which are alpha, beta, and gamma of which the isomer that is useful as an insecticide also has much application is called the lindane or otherwise it is called gammaxene that is the gamma isomer of benzene hexachloride has much use.

Background wave

Benzene hexachloride was first discovered in 1825 by Faraday. The Dutch chemist Lindane discovered or isolated the gamma isomer in 1912 hence the name Lindane is given to the gamma isomer of the compound benzene hexachloride. Whereby the gamma isomer isolated has shown that it possesses insecticidal properties and is more toxic than many other compounds.

The structural difference between alpha, beta, and gamma is in their orientation of the chlorine atoms concerning the ring of carbon atoms. The volatility of the gamma isomer of BHC is more than DDT. Mergamma A is a compound used for seed treatment and this compound contains 1 % Mercury and 20 percent lindane.

NEET Highest Scoring Chapters & Topics
This ebook serves as a valuable study guide for NEET exams, specifically designed to assist students in light of recent changes and the removal of certain topics from the NEET exam.
Download EBook

Also read -

Preparation of benzene hexachloride

Benzene hexachloride can be prepared by many methods, some of the methods for the preparation of benzene hexachloride are described below

  • In the presence of sunlight and in the absence of oxygen that is the reaction is done in a closed atmosphere where the benzene reacts with chlorine in presence of sunlight to form benzene hexachloride and a substitution catalyst may be used to increase the rate of this reaction.
  • Benzene hexachloride can be prepared by the photochlorination method where the isomers of hexachloride are formed, therefore to extract the gamma isomer the reaction mixture is treated with methanol or acetic acid. Whereby the alpha and the beta isomers of benzene hexachloride dissolve easily and we can easily separate gamma isomers from the reaction mixture. The following reaction shows the preparation of benzene hexachloride from benzene and chlorine.

C6H6+3Cl2 hv→ C6H6Cl6

Properties of benzene hexachloride

Benzene hexachloride is a chemical compound with the molecular formula C6H6Cl6 That means it contains 6 chlorine atoms in addition to the benzene ring. The molecular weight or molecular mass of this organic compound is 290.814 grams per mole with a density of 1.89. The melting point of benzene hexachloride is 113 degrees Celsius and the boiling point is 323 degrees Celsius.

BHC Structure

The image shown below describes the structure of benzene hexachloride that with the chemical formula C6H6Cl6. Benzene hexachloride is a Gamma isomer and it has a serious effect on human beings; it is a toxic compound. From the below structure of benzene hexachloride, we obtain that it is a compound that contains 6 carbon atoms, 6 hydrogen atoms, and 6 chlorine atoms that means the double bonds of benzene has been substituted with the chlorine compounds.

Structure of BHCStructure of BHC

Toxicity of benzene hexachloride

It is a highly toxic compound when it comes in contact with skin, eyes, etc. And also when it is inhaled the effects are very much. It has a serious effect on the nervous system so that further it may lead to the death of the individual who has suffered from the toxicity of benzene hexachloride. Lindane or gamma benzene hexachloride has been found that gets accumulated in the food chain whereby from animals to human beings and also from marine life.

Exposure to lindane may cause acute poisoning and which further affects the nervous system. Benzene hexachloride is a neurotoxin that causes toxicity by interfering with the functioning of neurotransmitters. It is also shown that serious exposure has been adversely affected liver functions in human beings. This also reported that it has effects on the kidneys of human beings and therefore it is a type of carcinogen as well. BHC insecticides are highly toxic organochlorine compounds.

In addition to the effects on human beings, it can also affect the environment as it is an organic pollutant. When this Pollutant persists in the environment the causes serious effects on the environment and also it will enter the food chain. When Lindane is present in soil it gets broken down into less harmful substances by the process of fungi and bacteria but this process is relatively slow so the use of this compound must be reduced thereby our environment can convert it into a less harmful substance. There are so many reports showing that in some countries the use of this gammaxene is reduced.

Also Read:

Uses of BHC

  • Gamma benzene hexachloride commonly known as limited is used as an insecticide.
  • It is present in some creams and shampoos for the treatment of lice infection.
  • It has application in the pharmaceutical industry.
  • It can be used for the treatment of scabies.
  • Benzene hexachloride is used as a weedicide therefore it is also used as a fertilizer.
  • Benzene hexachloride is used against domestic cockroaches.

Gamaxin powder uses

Lindane is known as gammaxene also called BHC, which has a wide application in the field of the agricultural industry and pharmaceutical industry. It is used as an insecticide and pesticide in the agricultural sector. But due to the high toxicity of this compound, some countries reduced its production. It is used in pharmaceuticals for the production of shampoos and creams for the infections caused by lice. And also for the treatment for the disease scabies, is a skin disease. Gammaxene powder used in horticulture. Gammaxene has now replaced the place of DDT due to its best results.

Also check-

NCERT Chemistry Notes:

Frequently Asked Questions (FAQs)

1. The chemical name of gammaxene?

Benzene hexachloride( BHC).

2. What is the formula of BHC?

C6H6Cl6.

3. What is BHC?

A type of polyhalogenated organic compound with the chemical formula C6H6Cl6 is BHC (Benzene hexachloride). It is obtained by the chemical reaction in presence of sunlight with benzene and chlorine. It is a white crystalline solid also called lindane and gammaxene with a wide application in the agriculture and pharmaceutical industry. It is widely used as an insecticide and pesticide. But due to high toxicity, the use of this compound in the agricultual sector has been reduced by many countries. The most insecticidal isomer of BHC is the gamma isomer that is called lindane. There are many other isomers for BHC. The one with the most extensive application is its gamma isomer.

4. What is the IUPAC name of benzene hexachloride?

1,2,3,4,5,6 Hexachlorocyclohexane.

5. What is the chemical name of gammexane?

Lindane.

6. How is BHC prepared in the laboratory?
BHC is prepared by photochlorination of benzene. This reaction involves exposing benzene to chlorine gas in the presence of ultraviolet light. The process adds six chlorine atoms to the benzene ring, breaking its aromaticity and forming the cyclohexane structure of BHC.
7. What role does UV light play in the preparation of BHC?
UV light initiates the radical chlorination reaction. It breaks the Cl-Cl bond in chlorine gas, forming chlorine radicals. These radicals then attack the benzene molecule, leading to a chain reaction that results in the addition of six chlorine atoms to form BHC.
8. How does the structure of BHC differ from benzene?
While benzene has a planar, aromatic structure with six carbon atoms in a ring, BHC has six chlorine atoms attached to the cyclohexane ring. This changes the geometry from planar to a three-dimensional structure, with chlorine atoms alternating above and below the ring plane.
9. What is the difference between technical grade BHC and pure γ-BHC (lindane)?
Technical grade BHC is a mixture of various isomers, typically containing 10-18% of the γ-isomer. Pure γ-BHC, or lindane, contains at least 99% of the γ-isomer. Lindane is more potent and has fewer environmental concerns compared to the technical grade mixture.
10. What is benzene hexachloride (BHC) and why is it important?
Benzene hexachloride (BHC) is an organochlorine compound with the chemical formula C6H6Cl6. It's important because it's a powerful insecticide used to control a wide range of pests in agriculture and public health. BHC is particularly notable for its effectiveness against soil-dwelling insects and its long-lasting residual action.
11. How does the solubility of BHC compare in water and organic solvents?
BHC is poorly soluble in water but highly soluble in organic solvents. This property is due to its non-polar nature, resulting from the presence of multiple chlorine atoms. This solubility profile affects its environmental behavior and application methods as an insecticide.
12. How does the structure of BHC contribute to its persistence in the environment?
The multiple carbon-chlorine bonds in BHC make it resistant to degradation. These strong bonds are not easily broken down by natural processes or microorganisms, leading to its long-lasting presence in soil and water. The cyclohexane ring structure also contributes to its stability.
13. Why is the γ-isomer of BHC (lindane) more effective as an insecticide?
The γ-isomer (lindane) is more effective because its molecular structure allows it to fit more precisely into insect nerve receptors, disrupting their nervous system more efficiently than other isomers. This structural specificity is key to its potent insecticidal activity.
14. How does BHC affect insect physiology?
BHC acts as a neurotoxin in insects. It interferes with the GABA (gamma-aminobutyric acid) receptor in the nervous system, leading to overstimulation of nerves. This causes rapid, uncontrolled impulses, resulting in paralysis and death of the insect.
15. What are the isomers of BHC and how do they differ?
BHC has eight stereoisomers, labeled α, β, γ, δ, ε, ζ, η, and θ. These isomers differ in the spatial arrangement of chlorine atoms around the cyclohexane ring. The γ-isomer, also known as lindane, is the most insecticidally active form.
16. What are the environmental concerns associated with BHC use?
BHC is a persistent organic pollutant (POP). It can accumulate in the environment and food chain due to its stability and lipophilic nature. This persistence raises concerns about long-term ecological impacts, including effects on non-target organisms and potential human health risks through bioaccumulation.
17. Why was BHC widely used despite its environmental concerns?
BHC was widely used due to its broad-spectrum insecticidal activity, long-lasting effects, and relatively low cost. It was effective against a wide range of pests in various applications, from agriculture to public health, making it a versatile and economical choice before its environmental impacts were fully understood.
18. What are the main degradation pathways for BHC in the environment?
BHC can degrade through several pathways in the environment:
19. How does the presence of BHC affect soil microbial communities?
BHC can have significant impacts on soil microbial communities:
20. What are the main metabolites of BHC in biological systems?
The metabolism of BHC in biological systems can produce several metabolites:
21. How does the melting point of BHC compare to that of benzene?
BHC has a much higher melting point than benzene. While benzene melts at 5.5°C, the various isomers of BHC have melting points ranging from 112°C to 310°C. This difference is due to the stronger intermolecular forces in BHC caused by the presence of chlorine atoms.
22. What is the significance of BHC's high melting point in its applications?
The high melting point of BHC contributes to its stability and persistence in the environment. In practical applications, it means BHC remains solid at room temperature, affecting its formulation and application methods as an insecticide. It also influences its environmental fate, as it's less likely to volatilize compared to more volatile pesticides.
23. How does the polarity of BHC compare to that of benzene?
BHC is more polar than benzene due to the presence of electronegative chlorine atoms. However, it's still considered relatively non-polar overall. This slight increase in polarity affects its solubility and environmental behavior, making it more soluble in organic solvents than in water, but more water-soluble than benzene.
24. What is the impact of BHC's polarity on its environmental distribution?
The moderate polarity of BHC allows it to be slightly soluble in water while still being lipophilic. This dual nature enables it to disperse in aquatic environments to some extent, but also accumulate in fatty tissues of organisms. This property contributes to its bioaccumulation in the food chain and its widespread environmental distribution.
25. How does the reactivity of BHC compare to that of benzene?
BHC is generally less reactive than benzene. The presence of chlorine atoms and the loss of aromaticity make BHC resistant to many reactions that benzene readily undergoes, such as electrophilic aromatic substitution. This reduced reactivity contributes to its persistence in the environment.
26. Why is the γ-isomer of BHC more biodegradable than other isomers?
The γ-isomer (lindane) is more biodegradable due to its molecular configuration. The arrangement of chlorine atoms in the γ-isomer makes it more susceptible to enzymatic attack by certain microorganisms. This spatial arrangement allows for easier access to the carbon-chlorine bonds, facilitating biodegradation.
27. How does the vapor pressure of BHC affect its environmental behavior?
BHC has a relatively low vapor pressure, which means it doesn't readily evaporate at room temperature. This property affects its environmental fate by:
28. What is the significance of BHC's octanol-water partition coefficient?
The octanol-water partition coefficient (Kow) of BHC is relatively high, indicating its tendency to partition into organic phases rather than water. This property is significant because it:
29. How does the structure of BHC influence its insecticidal activity?
The insecticidal activity of BHC, particularly the γ-isomer, is influenced by its structure in several ways:
30. What are the main differences between BHC and DDT as insecticides?
While both BHC and DDT are organochlorine insecticides, they differ in several aspects:
31. How does the chirality of BHC isomers affect their properties?
The chirality of BHC isomers significantly influences their properties:
32. What are the main industrial uses of BHC besides insecticides?
While BHC is primarily known as an insecticide, it has had other industrial applications:
33. How does the molecular weight of BHC influence its environmental behavior?
The molecular weight of BHC (290.83 g/mol) influences its environmental behavior in several ways:
34. What role does electron delocalization play in the properties of BHC?
Electron delocalization in BHC is limited compared to benzene:
35. How does the stereochemistry of BHC isomers affect their biological activity?
The stereochemistry of BHC isomers significantly influences their biological activity:
36. What are the key differences in the infrared (IR) spectra of benzene and BHC?
The IR spectra of benzene and BHC differ significantly:
37. How does the boiling point of BHC compare to that of benzene, and why?
BHC has a much higher boiling point than benzene:
38. What are the main challenges in the analytical detection of BHC in environmental samples?
Detecting BHC in environmental samples poses several challenges:
39. How does the electron-withdrawing nature of chlorine atoms in BHC affect its chemical properties?
The electron-withdrawing chlorine atoms in BHC influence its properties:

Articles

Back to top