Chemical Properties Of Carbon Compounds

Key Notes:

Combustion:

  • Carbon compounds, like hydrocarbons, burn in the presence of oxygen to produce carbon dioxide, water, heat, and light.
  • Complete Combustion: Occurs with sufficient oxygen supply, producing carbon dioxide and water.
    • Example: Methane CH4 + 2O2 → CO2 + 2H2O → CO2 ​+ 2H2​O
  • Incomplete Combustion: Limited oxygen supply results in carbon monoxide or soot.
    • Example: Ethane in limited oxygen produces carbon monoxide.

Oxidation:

  • Carbon compounds can undergo oxidation reactions to form alcohols, aldehydes, acids, etc.
  • Oxidizing agents like alkaline potassium permanganate (KMnO₄) or acidic potassium dichromate (K₂Cr₂O₇) can oxidize ethanol to ethanoic acid.

Addition Reactions (in Unsaturated Hydrocarbons):

  • Occurs with alkenes and alkynes due to the presence of double or triple bonds.
  • Hydrogenation: Addition of hydrogen to unsaturated hydrocarbons to form saturated ones using a nickel or platinum catalyst.
    • Example: Ethene + Hydrogen → Ethane.
  • Halogenation: Addition of halogens like chlorine or bromine.
    • Example: Ethene + Bromine → 1,2-Dibromoethane.

Substitution Reactions (in Saturated Hydrocarbons):

  • Involves replacing one or more hydrogen atoms in an alkane with another atom (e.g., halogen).
  • These reactions are common in alkanes due to their stability.
    • Example: Methane + Chlorine (in the presence of sunlight) → Chloromethane + Hydrogen Chloride.

Esterification:

  • Reaction between an alcohol and a carboxylic acid to form an ester and water.
  • Esters have a fruity smell and are used in perfumes and flavorings.
    • Example: Ethanol + Ethanoic Acid → Ethyl Acetate + Water.

Saponification:

  • Hydrolysis of esters (fats or oils) in the presence of a base (like NaOH) to produce soap and glycerol.
    • Example: Triglyceride + Sodium Hydroxide → Soap + Glycerol.

Polymerization:

  • Small carbon compounds (monomers) join together to form long chains (polymers).
  • Can be Addition Polymerization (like polyethylene) or Condensation Polymerization (like nylon).

Dehydration:

  • Removal of water molecules from a compound, typically using a dehydrating agent like concentrated sulfuric acid.
  • Example: Ethanol can be dehydrated to form ethene.

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