Lecture Notes: Memorization Techniques and Chemistry Concepts

Key Concepts for Chemistry

• Memorization Techniques: Essential for mastering this unit.
• Electron Transfer:
  • Single arrow indicates a single electron transfer.
  • Double arrow indicates movement of both electrons.
  • Always draw the movement of electrons, not positive ions.

Writing Conventions

• Radicals: Indicated by a big dot, means valence shell isn't full.
• Complex Charges and Ligands:
  • Complex charge depends on ligands.
  • Dashed lines indicate delocalized electrons, not full bonds.

Alkane Reactions

• Terminology:
  • Catenation: Ability of an element to bond with itself, crucial in organic chemistry.
• Bond Stability:
  • Carbon-carbon bonds: 348 kJ/mol.
  • Carbon-hydrogen bonds: 414 kJ/mol.
• Combustion:
  • Complete: Produces CO2.
  • Incomplete: Produces carbon monoxide, can lead to poisoning.

Reaction Types

• Heterolytic vs. Homolytic Splitting
  • Heterolytic: Uneven split, one side positive, one negative.
  • Homolytic: Creates radicals with equal breakage.

Alkane Mechanisms

• Mechanism Steps:
  • Initiation: Radical creation.
  • Propagation: Continued radical presence leading to further reactions.
  • Termination: Radicals are neutralized.
• Role of UV Light: Breaks weak bonds such as chlorine.

Alkene Reactions

• Stability:
  • Single bonds are more stable than double bonds.
• Memorization:
  • Nickel catalyst at 150 degrees for certain reactions.

Alcohol Reactions

• Combustion: More carbon bonds mean more energy stored.
• Oxidation:
  • Tertiary alcohols hard to oxidize due to steric hindrance.
  • Formation of aldehydes and carboxylic acids.

Condensation Reactions

• Removal of small molecules during the reaction.
• Esterification: Reaction between alcohol and carboxylate.

Halogen and Alkane Reactions

• Nucleophile and Electrophile:
  • Nucleophiles love positive (are negative themselves).
  • Electrophiles love negative (are positive themselves).

Benzene Reactions

• Electrophile replaces H+ ion in reactions.