Alkanes key terms

Fractional Distillation

A separation technique that exploits differences in boiling points to isolate components of a liquid mixture, such as crude oil, into distinct fractions.

Crude Oil Fractions

Subsets of crude oil separated by fractional distillation, each with a characteristic boiling range and composition, ranging from light gases to heavy residuum.

fractional distillation

A process that separates a mixture into its component parts, or fractions, based on differences in boiling points.

intermolecular forces

Forces of attraction or repulsion between neighboring particles, which influence the physical properties of substances, such as boiling and melting points.

cracking

A chemical process that breaks down larger hydrocarbon molecules into smaller, more useful ones, often using heat and catalysts.

useful hydrocarbons

Hydrocarbons that are more valuable for applications such as fuels and feedstocks, produced through processes like cracking.

Cracking

A thermal or catalytic process that breaks large hydrocarbon molecules into smaller ones, typically producing alkenes and smaller alkanes.

Thermal Cracking

Cracking carried out at high temperatures (≈450–750 °C) without a catalyst, resulting in the cleavage of C–C bonds in long-chain alkanes to form smaller alkanes and alkenes.

complete combustion

The reaction of a hydrocarbon with oxygen to produce carbon dioxide and water, releasing energy.

alkane

A saturated hydrocarbon with the general formula CnH2n+2, where n is the number of carbon atoms.

internal combustion engine

A type of engine that burns fuel to create power, producing exhaust gases as pollutants.

pollutants

Substances produced during combustion that can harm the environment and human health, such as carbon monoxide and nitrogen oxides.

catalytic converter

A device used in vehicles to reduce harmful emissions by converting pollutants into less harmful substances.

pollutant

A substance that contaminates the environment and can cause harm to living organisms and ecosystems.

sulfur dioxide removal

The process of eliminating sulfur dioxide from flue gases, often using methods such as scrubbing with alkaline solutions.

flue gas desulfurization

A technology used to remove sulfur dioxide from the exhaust flue gases of fossil-fuel power plants, typically involving chemical reactions with absorbents.

free-radical substitution

A reaction mechanism where free radicals replace atoms in a molecule, typically involving initiation, propagation, and termination steps.

initiation step

The first stage in free-radical substitution where free radicals are generated, often requiring energy such as ultraviolet light.

chlorination

The process of substituting hydrogen atoms in methane (CH₄) with chlorine atoms (Cl) to form chlorinated hydrocarbons.

free-radical substitution

A reaction mechanism involving initiation, propagation, and termination steps, where free radicals are formed and react to substitute atoms in a molecule.

ultraviolet light

Ultraviolet light provides the energy necessary to break the bonds in chlorine molecules, leading to the formation of chlorine radicals.

radical formation

Radical formation occurs when ultraviolet light initiates the breaking of bonds in chlorine, resulting in reactive chlorine radicals that can participate in further chemical reactions. In Chlorination of alkanes, radical formation is used to explain explain why ultraviolet light is needed for radical formation with A-Level Chemistry precision.