Introduction to Organic Chemistry

• Focus on organic compounds, specifically those containing carbon.
• Carbon typically forms four bonds.

Bonding Preferences of Elements

• Hydrogen: Prefers one bond.
• Beryllium: Prefers two bonds.
• Boron: Prefers three bonds.
• Carbon: Prefers four bonds.
• Nitrogen: Prefers three bonds in organic chemistry.
• Oxygen: Prefers two bonds.
• Halogens (Fluorine, Chlorine, Bromine, Iodine): Typically form one bond.

Lewis Structures

• Help us visualize molecule structure.
• Example: Water (H2O) and Methyl Fluoride (CH3F).
• Polar Bonds: Carbon-Fluorine bond is polar; Carbon-Hydrogen bond is non-polar.

Types of Covalent Bonds

• Non-polar Covalent Bond: Equal sharing of electrons.
• Polar Covalent Bond: Unequal sharing of electrons (e.g., Hydrogen-Fluorine).
• Hydrogen Bonds: Special type of polar covalent bond.

Ionic vs Covalent Bonds

• Ionic Bonds: Electrons are transferred (e.g., Sodium and Chlorine).
• Covalent Bonds: Electrons are shared.

Alkanes and Their Formulas

• Saturated organic compounds.
• Follow the formula CnH2n+2.
• Examples: Methane (CH4), Ethane (C2H6), Propane (C3H8), etc.

Drawing Lewis Structures for Alkenes and Alkynes

• Alkenes: Contain at least one double bond. Example: Ethene (C2H4).
• Alkynes: Contain at least one triple bond. Example: Ethyne (C2H2).

Bond Length and Strength

• Carbon-Carbon Single Bond: Longest (154 pm).
• Carbon-Carbon Double Bond: 133 pm.
• Carbon-Carbon Triple Bond: Shortest (120 pm).
• Triple Bonds: Strongest.

Sigma and Pi Bonds

• Sigma Bonds: Stronger than pi bonds.
• Single bond: 1 sigma bond.
• Double bond: 1 sigma + 1 pi bond.
• Triple bond: 1 sigma + 2 pi bonds.

Bond Order

• Single bond: Order 1.
• Double bond: Order 2.
• Triple bond: Order 3.

Hybridization

• Helps determine the shape of molecules.
• sp3: Tetrahedral.
• sp2: Trigonal planar.
• sp: Linear.

Formal Charge Calculation

• Formula: Valence electrons - (Bonds + Lone pairs).
• Example: Sulfur and Nitrogen atoms.

Functional Groups and Organic Compounds

• Alcohols: Ethanol (CH3CH2OH).
• Aldehydes: Ethanal (CH3CHO).
• Ethers: Dimethyl ether (CH3OCH3).
• Ketones: Propanone (CH3COCH3).
• Esters and Carboxylic Acids: Methyl ethanoate and pentanoic acid.

Expanding Condensed Structures

• Practice with various structures to better understand organic compound structures.