Carbon is unique because it can form four covalent bonds with other atoms, including itsell Th property allows carbon to create chains, branched structures, and rings. It can also form single, double and triple bonds, making it versatile in forming millions of organic compounds
Hydrocarbons are organic compounds made up entirely of carbon and hydrogen atoms They are drocarbons are used as fuels and raw materials for producing plastics and chemicals.
Saturated hydrocarbons, or alkanes, have only single bonds between carbon atomis. They are mically less reactive. Unsaturated hydrocarbons include alkenes and alkynes, which have double of mple bonds, making them more reactive. For example, ethane (C.Mo) is saturated, while
The general formula for alkanes is CnH2n+2, where nn is the number of carbon atoms. For ample, if n=3, the alkane is propane (CH). This formula works for all straight-chain and branched
Hydrocarbons are named by identifying the longest continuous carbon chain as the parent structure. Prefixes indicate the number of carbons, and numbers show the positions of branches or functional groups. For example, CH3-CH(CH3)-CH, is named 2-methylpropane. 7.
The IUPAC name of CHa is methane. It is the simplest alkane with one carbon atom and four ydrogen atoms. Methane is a major component of natural gas.
The IUPAC name of CH3-CH2-CH3 is propane. It is an alkane with three carbon atoms in a straight Chain and is commonly used as a fuel for cooking and heating
Alkanes are saturated hydrocarbons containing only single bonds between carbon atoms. They are non-polar and chemically stable. Examples include methane (CH4), ethane (CH), and butane (Can). Alkanes are commonly used as fuels.
The physical state of alkanes depends on their molecular size. Lower alkanes like methane (CH and ethane (C₂H₂) are gases, middle alkanes like hexane (C₂H₂) are liquids, and higher alkanes like paraffin ax are solids.
Cracking is the process of breaking larger hydrocarbons into smaller alkanes and allenes using eat or catalysts, it is used on the petroleum industry to produce gasoline and other fuels For example: .
Alkenes can be converted into alkanes by adding hydrogen in the presence of a metal catalyst such as nickel for platinum. This process is called hydrogenation. Ni HC-CH+H (Ethene) HC-CH (Ethane) 200-300°C Example:
Alkynes can be reduced to alkanes by adding hydrogen gas in the presence of a metal catalyst. This reaction involves breaking two in bonds to form a saturated hydrocarbon Example: Ni → 200-3000C CH CH+2H₂ (Ethyne) HC-CH3 (Ethane) Reactions of Alkanes: Combustion
Combustion is the reaction of alkanes with oxygen, producing carbon dioxide, water, and energy It is highly exothermic, making alkanes valuable as fuels. Example: CH202 CO₂ + 2H₂O + Heat
Incomplete combustion occurs when oxygen is limited, leading to the production of carbon monoxide (CO) or carbon. This is dangerous as carbon monoxide is toxic. Example: 2CH+3022CO + 4H2O + Heat
Alkanes are used as fuels because they burn readily in oxygen to release large amounts of energy. For example, methane is a primary fuel in natural gas, and propane is used in liquefied petroleum gas (LPG).
Halogenation is a substitution reaction where a hydrogen atom in an alkane is replaced by a halogen atom under ultraviolet (UV) light. Example: CH+Cl₂CH₂-CI + H-CI Methane reacts with chlorine to form methyl chloride. Reactions of Alkanes: Halogenation
When methane (CH4) reacts with chlorine gas (Cl2) under ultraviolet (UV) light, a substituti reaction occurs. This reaction can produce a series of chlorinated products depending on the extent of the reaction.
UV light provides energy to break the chlorine molecule (Cl.) into two reactive chlorine atoms, inininating the halogenation reaction.
Methane is used as a clean and efficient fuel in homes (natural gas) and as a raw material in the production of methanol, ammonia, and other chemicals.
Cracking is a process used to break large hydrocarbons from crude oil into smaller alkanes and alkenes. It produces useful products like gasoline, diesel, and ethene for plastics.
The boiling points of alkanes increase with chain length because larger molecules have stronger intermolecular forces, requiring more energy to separate.
Alkanes are considered inert because their carbon-carbon and carbon-hydrogen bonds are strong and non-polar, making them unreactive under normal conditions.
Burning alkanes produces carbon dioxide, contributing to global warming. Incomplete combustion can produce carbon monoxide, which is toxic and harmful to the environment.
Isomers are compounds with the same molecular formula but different structures. For example, butane (C4H10) has two isomers: n-butane (a straight chain) and is obutane (a branched chain).
