Carbon And Its Compounds

In methane, the sp³ orbitals are formed. They arrange themselves so that they are as far apart as possible and this results in a tetrahedral arrangement. The bond angle of this arrangement is 109.28’

The formula for alkenes is: C_nH_2n-2.

For n = 5, C₅H_2×5-2 = C₅H_10, which is the formula for alkene.

Freon-11 is commonly known as tri-chloro-fluoro-methane

Natural rubber is from the monomer isoprene (2-methyl-1,3-butadiene), which is a conjugated diene hydrocarbon.

Carbon can form different allotropes due to its valency. Out of all the allotropes, graphite is a conductor of electricity as it is the most stable form of carbon. It conducts electricity due to delocalization of pi bond electrons which are free to move.

Sulphur acts as an accelerator in this process which modify the polymer by forming cross-links between each polymer chains.

After identifying the longest chain of carbon as the parent chain, the number of saturated hydrocarbons will determine the prefix.

The prefixes are given below:

The lowest number should be assigned to the double bond.

Alkanes, alkenes, and alkynes are simple hydrocarbon chains with no functional groups. Alkanes are the carbon chain which has only single bonds. Alkenes have at least one double bond and alkynes have at least one triple bond.

The general formula for Alkanes: C_nH_2n+2
The general formula for Alkenes: C_nH_2n
The general formula for Alkynes: C_nH_2n-2

Hydrocarbons are the organic compounds which are comprised of carbon & hydrogen. There are our types of hydrocarbon namely alkane, alkene, alkyne, and alkynes. It is mainly found in fossil fuels. Some examples are methane, ethane, butane.

International Union of Pure and Applied Chemistry (IUPAC). IUPAC created the chemical nomenclature which is used to generate systematic names for chemical compounds.

Vulcanization is a chemical process for converting natural rubber into the more durable material by heating them with sulphur which acts as an accelerator. Sulphur modify the polymer by forming cross-links between individual polymer chains. Vulcanized materials are less sticky and have superior mechanical properties.

Advantages of vulcanized rubber are:

● Excellent resilience i.e.it returns to the original shape, when the deforming load is removed

● Higher resistance to oxidation, wear and tear abrasion

● Resistant to organic solvents (petrol, benzene), fats and oils

● Good tensile strength and extensibility

● Low water absorption tendency and a better insulator

Buckminster fullerene is a molecule of carbon in the form of a hollow sphere. It consists of 60 carbon atoms that link together to form a hollow cage-like structure. It consists of 32 faces out of which 20 are hexagons and 12 are pentagons.

Carbon atom has 4 valence electrons with electronic configuration 1s²2s²2p². In order to attain stability, it forms single, double and triple bonds with other atoms. If all bonds are single bonds then its geometry is tetrahedral.

Freon is chlorofluorocarbon refrigerant that contains carbon, chlorine, and fluorine. They are mainly used in fridges & air conditioners and is one of the main reason for the depletion of the ozone layer. Freon-10 is one example which is carbon tetrachloride.

Friedrich Wohler was the first to prepare Urea, an organic compound, by heating ammonium sulphate with potassium cyanate. The chemical reaction involved:

CNG stands for Compressed Natural Gas. It is used as a fuel in vehicles and is considered a clean fuel as compared to petrol and diesel.

Acrylonitile monomer is used to make orlon.

IUPAC name of Isobutane (C₄H₁₀)is 2-methylpropane.

Allotropes are the different physical forms in which an element can exist. Diamond, Graphite, charcoal, and fullerene are some allotropes of carbon.

PAN stands for Poly Acrylic Nitrile which is also known as Creslan-61. It is used to make wool, fiber etc.

PVC (Poly Vinyl Chloride) is made from the polymerization of vinyl chloride and is mainly used to make pipes and tubes.

Catenation is the binding of an element to itself through covalent bonds to form chain or ring molecules. Carbon is the most common element that exhibits catenation. It can form long hydrocarbon chains and rings like benzene.

(i) C₅H₁₂ : Pentane

(ii) C₄H₈ : 2-Methylpropene (isobutene)

(iii) C₃H₄ : Propyne

Freons are Chlorofluorocarbons which are made up of chlorine, carbon, and fluorine. They are used as refrigerants in several electronic devices like refrigerators and air conditioners. They are also used as aerosol propellants.

CNG refers to Compressed Natural Gas which consists of methane whereas Liquefied Petroleum Gas is a mixture of propane & butane. Carbon dioxide and water vapour are the only byproducts when CNG is burnt. In LPG, three or four carbon bonds are present thus releasing carbon dioxide in excess along with other harmful gases. Moreover, CNG is lighter gas as compared to LPG. So in case of leakage, CNG gets mixed with atmosphere nut LPG will get oxidized and can cause an accident. Therefore CNG is considered better fuel than LPG.

In Diamond. each carbon atom is covalently bonded with four other carbon atoms along the four corners of a regular tetrahedron in three dimensional. Therefore diamond is hard due to strong covalent bonds present in it. Whereas in graphite, carbon atoms are bonded together in flat layers by strong covalent bonds in a regular hexagon. But these layers are held together by Van der Waal's forces which are much weaker as compared to the covalent bonds. This is the reason why graphite is soft and slippery.

Importance of hydrocarbon are:

● Hydrocarbons are the primary source of energy in today’s world. Methane in CNG and Propane and butane in LPG are different forms of hydrocarbons.

● Freons, a form of hydrocarbon, are used as refrigerants and aerosol propellants.

● They are also used in the manufacturing of polymers like polythene, polystyrene and so on.

● They are used in to manufacture drugs and dyes and also serve as lubricating oil and grease.

Hydrocarbons are made up of only carbon and hydrogen. There are four types of hydrocarbon: Alkanes, alkenes, alkynes, and arenes.

Alkanes: Alkanes are organic compounds that consist entirely of single-bonded carbon and hydrogen atoms and lack of any functional group. They are also referred to as saturated hydrocarbon.

Alkenes: An alkene is an unsaturated hydrocarbon that consists of at least one carbon-carbon double bond.

Alkynes: An alkyne is an unsaturated hydrocarbon containing at least one carbon-carbon triple bond.

Arenes: Arenes are aromatic hydrocarbons (most commonly based on benzene rings) such as benzene and methylbenzene.

Graphite is a crystalline allotrope of carbon and is black and opaque. It is soft and slippery and is a good conductor of electricity as well. It is used in the following ways:

● Graphite is used to make electrodes of a battery.

● It acts as a lubricator in the steel making process.

● Natural amorphous and fine flake graphite are used in brake linings or brake shoes for heavier (non-automotive) vehicles and became important with the need to substitute for asbestos.

● It is used to make pencils.

The importance of carbon is as follows:

● Carbon is present in the form of hydrocarbon in fuels such as CNG, LPG etc which are the main source of energy.

● Carbon is used in the process of polymerization so as to form different polymers which are light weight as well as durable.

● Carbon dioxide, a form of carbon, is used by plants for the process of photosynthesis which provides energy to plants and thus sustaining the eco system.

● Carbon is the most common element that exhibits catenation thus forming different allotropes of carbon such as graphite, charcoal, and diamond which are used in different fields.

(i)iso-octane:

Is an organic compound with the formula (CH₃)₃CCH₂CH(CH₃)₂. It is one of several isomers of octane (C₈H₁₈).

Its IUPAC name is 2,2,4-Trimethylpentane.

(ii)

For the given structure IUPAC name is 2-methyl-prop-1-ene.

(iii) neo-pentane:

It is one of the three structural isomers with the molecular formula C₅H₁₂ (pentanes).

Its IUPAC name is 2,2-dimethylpropane.

(iv)

For the given structure IUPAC name is 2-bromo,3-chlorobutane.

Plastic is a synthetic material made up of a wide range of organic polymers like polythene, PVC, nylon, etc. that can be molded in any shape while it is soft.

Main plastic polymers are:

i) Polythene: Polythene is formed by polymerization of ethene molecules.

ii) Poly Vinyl Chloride (PVC): It is formed by polymerization of vinyl chloride.

iii) Poly Acrylic Nitrile: It is formed by polymerization of vinyl cyanide.

Uses of diamond are:

● Diamond is used in jewellery due to its durability and luster.

● It is used to cut, grind or drill other materials in industries because it is one of the hardest materials.

● Diamond can also be used in making tungsten wires. The diamond dies are used for the process of making the wires using the lab equipment.

● Diamonds can be used for engraving stones to various other metals. The various stones that can be engraved are granite, quartz, etc.

Uses of fullerene are:

● Fullerenes are strong drug absorbent.

● It is used in artificial photosynthesis.

● Due to its spherical structure, it acts as a lubricant.

● It is also used in cosmetic industry.

Freons are Chlorofluorocarbons which are made up of chlorine, carbon, and fluorine. When carbon tetrachloride reacts with hydrogen fluoride in the presence of SbCl₅ then Freon-11 is formed.

CCl₄ + HF → CCl₃F + HCl (in presence of SbCl₅)

The system contains a body, CFC, a number, 01234, and an alphanumeric suffix, a: CFC-01234a

● The body stands for the group type

● The number stands for the molecular formula

● The suffix stands for different isomers

Example:

CFC-12b1 has no double bonds, only 1 carbon atom, no hydrogen atoms, 2 fluorine atoms, one chlorine atom replaced by bromine and no isomers = Bromochlorodifluoromethane

If it is a cyclic structure the number is prefixed with a "C" for cyclic. Sometimes some other bodies are found like FC (fluorocarbon), HC (Halocarbon) or R(refrigerant).

Polymers are large molecules made up of many small and identical repeating units joined together by covalent bonds. Synthetic polymers are the polymers made artificially in industries from chemical industries. Synthetic polymers include :

i) Nylon-66: Nylon 66 is synthesized by polycondensation of hexamethylenediamine and adipic acid.

n HOOC-(CH₂)₄-COOH + n H₂N-(CH₂)₆-NH₂→ [-OC-( CH₂)₄-CO-NH-(CH₂)₆-NH-]_n + (2n-1) H₂O

It is used in fibers for textiles and carpets and molded parts.

ii) Terylene: It is formed by esterification of ethylene glycol and terephthalic acid is conducted directly at moderate pressure and high temperature. Water is eliminated in the reaction, and it is also continuously removed by distillation
n C₆H₄(CO₂H)₂ + n HOCH₂CH₂OH→[(CO)C₆H₄(CO₂CH₂CH₂O)]_n + 2n H₂O

It is used to make plastic bottles which contain water and soft drinks.

iii) Plastic: Plastic is a synthetic material made up of a wide range of organic polymers like polythene, PVC, nylon etc. that can be molded in any shape while it is soft.

Main plastic polymers are:

Polythene: Polythene is formed by polymerization of ethene molecules. It is used to make bags, tubes, pipes.

Poly Vinyl Chloride (PVC) : It is formed by polymerization of vinyl chloride. It is used to make tubes and pipes.

Poly Acrylin Nitrile : It is formed by polymerization of vinyl cyanide. It is used to make wool and fibres.

iv) Synthetic Rubber: Synthetic rubber is any artificial elastomer which is durable as well as has greater resistance. They are made up of 2,1-dimethyl-1,3-butadiene and carbon dioxide in presence of sodium as a catalyst. It is used to make tyres-tubes, medical instruments, tanks, tubes etc.

(i) Freon: Freon is choloroflurocarbon refrigerant that contain carbon, chlorine and fluorine. They are mainly used in fridges & air conditioners and is one of the main reason for the depletion of ozone layer. Freon-10 is one example which is carbon tetrachloride. They are used as refrigerants in several electronic devices like refrigerators and air conditioners. They are also used as aerosol propellants. . When carbon tetrachloride reacts with hydrogen fluoride in the presence of SbCl₅ then Freon-11 is formed.

CCl₄ + HF → CCl₃F + HCl (in presence of SbCl₅)

(ii) CNG: CNG refers to Compressed Natural Gas which consists of methane. Carbon dioxide and water vapour are the only byproducts when CNG is burnt. It is light gas and when leaked gets mixed with the atmosphere. It is used as a fuel in vehicles and is a clean gas as it release low level of carbon dioxide.

(iii) Natural Rubber: Natural rubber is made up of a milky, runny material called latex obtained from stem of rubber tree. It consists of polymers of isoprene. Vulcanization is a chemical process for converting natural rubber into more durable material by heating them with sulphur which acts as an accelerator. Sulphur modify the polymer by forming cross-links between individual polymer chains. Vulcanized materials are less sticky and have superior mechanical properties.

Rubber is used for cements, for adhesive, insulating, and friction tapes; and for crepe rubber used in insulating blankets and footwear.

The rules used in nomenclature of alkanes are:

● Select the longest straight chain of carbon atoms in the molecular structure - this gives the parent name of the compound.

● Recognize any substituent on the longest chain. There are usually the following alkyl substituents:

● Number the carbon atoms on the straight chain, such that those bearing the substituent would have the lowest number.

● If there are two or more same substituent, use the prefixes: di- for two; tri-for three and tetra- for four, before the name of the substituent.

● If there are two substituents on the same carbon, then the position of that carbon is indicated twice before the names of the substituents.

● Write the names of the compound as one word, separate numbers from substituents groups and prefixes with a hyphen and numbers from each other with a comma .

● The position of carbon bearing the substituents is written first, followed by prefixes, then the name of substituents in alphabetical order, then finally the parent name.

(i) Neopentane : 2,2-dimethylpropane (C₅H₁₂)

(ii) Isopentane : 2-methylebutane (C₅H₁₂)

(iii) 1, 3-dichoropropane: C₃H₆Cl₂

(iv) 3-Ethyl-4-MethylHexane:

(v) 3-Methyl-1-butene