GreaLet’s break it down clearly:
Saturated Hydrocarbons
- Definition: Hydrocarbons in which all carbon–carbon bonds are single bonds (C–C).
- Bonding: Each carbon is bonded to as many hydrogen atoms as possible (hence “saturated” with hydrogen).
- General formula:
- Alkanes: CₙH₂ₙ₊₂
- Hybridization: sp³ hybridization (tetrahedral geometry).
- Examples: methane (CH₄), ethane (C₂H₆), propane (C₃H₈).
- Properties:
- Less reactive (mainly combustion and substitution reactions).
- Higher stability.
- Found in natural gas, petroleum, and waxes.
Unsaturated Hydrocarbons
- Definition: Hydrocarbons containing at least one double (C=C) or triple (C≡C) bond between carbon atoms.
- Types:
- Alkenes (C=C, double bonds) → general formula CₙH₂ₙ
- Alkynes (C≡C, triple bonds) → general formula CₙH₂ₙ₋₂
- Aromatic hydrocarbons (benzene rings) → delocalized π bonds.
- Hybridization:
- sp² (alkenes, aromatic)
- sp (alkynes)
- Examples: ethene (C₂H₄), ethyne (C₂H₂), benzene (C₆H₆).
- Properties:
- More reactive (due to π bonds).
- Undergo addition reactions (hydrogenation, halogenation).
- Important in making polymers (e.g., polyethylene, PVC).
Key Differences
Feature Saturated Hydrocarbons Unsaturated Hydrocarbons C–C bonds Only single bonds (C–C) At least one double (C=C) or triple (C≡C) Hydrogen content Maximum possible (saturated) Less hydrogen (unsaturated) Formula CₙH₂ₙ₊₂ (alkanes) CₙH₂ₙ (alkenes), CₙH₂ₙ₋₂ (alkynes) Hybridization sp³ (tetrahedral) sp² (planar), sp (linear) Reactivity Relatively less reactive More reactive (π bonds break easily) Examples Methane, Ethane, Propane Ethene, Ethyne, Benzene
In simple terms:
- Saturated = “full of hydrogens,” stable, single bonds only.
- Unsaturated = “not full,” has double/triple bonds, more reactive.