Hydrocarbon Reactions Overview

Hydrocarbon Reactions

• Pyrolysis/Cracking: Higher alkanes are converted into lower alkanes through a process called pyrolysis or cracking.

• Hydrogenation: Double bonds are reduced by hydrogenation, typically using hydrogen (H₂) and a catalyst like nickel (Ni).

• Stability of Alkenes: The stability of alkenes is directly proportional to the number of alkyl groups attached to the double bond.

Alkane Properties

• Structural Isomers: Different structural arrangements of the same molecular formula (e.g., different branches of an alkane).

• Branching: The presence of branches on a carbon chain affects properties such as boiling point and density (branched alkanes generally have lower boiling points). This is significant for comparing properties during reactions.

Additional Reactions

• Chlorination/Bromination: Chlorination and bromination of alkanes can form various mono-substituted products. The reaction produces only one single type of product in each scenario.

• Combustion: Alkanes undergo complete combustion in the presence of oxygen (O₂) to produce carbon dioxide (CO₂) and water (H₂O).

• Alkene Formation: Alkenes can be generated by removing hydrogen from alkanes

• Isomerization: Conversion of one isomer to another, like converting n-butane to 2-methylpropane.

Other Concepts

• Enantiomers: Enantiomers, mirror image isomers, are distinct compounds and can't be separated by fractional distillation.
• Cis-trans isomers: Cis and trans isomers exist because the rotation around a carbon-carbon double bond is hindered. This affects the placement of substituents relative to the bond axis.
• Aromatic Compounds: Aromatic compounds are cyclic, planar molecules that possess delocalized sigma and pi bonds, influencing their chemical reactivity compared to other ring compounds.
• Iodination of alkanes : Iodination of alkanes is a reversible process.