Reactions of Alkenes and Alkynes: Combustion and Addition

This page covers the fundamental reactions of alkenes and alkynes, focusing on combustion and addition reactions. These reactions are crucial in understanding the behavior and applications of unsaturated hydrocarbons in organic chemistry.

Combustion Reactions

Reakcje spalania alkanów alkenów i alkinów are important processes in organic chemistry. The document outlines three types of combustion reactions:

1. Complete combustion: CₙH₂ₙ + (3n/2)O₂ → nCO₂ + nH₂O
2. Partial combustion: CₙH₂ₙ + nO₂ → nCO + nH₂O
3. Incomplete combustion: CₙH₂ₙ + (n/2)O₂ → nC + nH₂O

Example: For ethene (C₂H₄), complete combustion would be: C₂H₄ + 3O₂ → 2CO₂ + 2H₂O

Addition Reactions

Reakcja addycji alkenów przykłady and reakcja addycji alkinów are discussed in detail. These reactions involve the addition of atoms or molecules to unsaturated compounds.

Hydrogenation

The addition of hydrogen to alkenes and alkynes is catalyzed by platinum:

• CH₂=CH₂ + H₂ → CH₃-CH₃ (ethene to ethane)
• CH≡C-CH₃ + H₂ → CH₂=CH-CH₃ (propyne to propene)

Highlight: Alkiny są bardziej reaktywne od alkenów in hydrogenation reactions, often requiring less harsh conditions.

Halogenation

The addition of halogens (X₂) to alkenes and alkynes:

• CH₂=CH₂ + Cl₂ → CH₂Cl-CH₂Cl (1,2-dichloroethane)
• CH≡C-CH₃ + 2Br₂ → CHBr₂-CBr₂-CH₃ (1,1,2,2-tetrabromopropane)

Vocabulary: Bromowanie alkenów refers to the addition of bromine to alkenes, forming dibromoalkanes.

Hydrohalogenation

The addition of hydrogen halides (HX) to alkenes and alkynes follows Markovnikov's rule:

• CH₃-CH=CH₂ + HCl → CH₃-CHCl-CH₃ (2-chloropropane)

Definition: Markovnikov's rule states that in hydrohalogenation, the halogen attaches to the carbon with fewer hydrogen atoms.