Organic Chemistry Overview

Introduction

• Focus: Organic compounds containing carbon atoms.
• Carbon typically forms four bonds.

Bonding Preferences by Element

• Hydrogen: 1 bond
• Beryllium: 2 bonds
• Boron: 3 bonds
• Carbon: 4 bonds
• Nitrogen: 3 bonds
• Oxygen: 2 bonds
• Halogens (F, Cl, Br, I): Typically 1 bond

Lewis Structures

• Water (H₂O): Oxygen forms two bonds with hydrogen.
• Methyl Fluoride (CH₃F): Carbon forms four bonds (with F and H).
  • Carbon-fluorine bonds are polar due to electronegativity differences.

Bond Polarity

• Polar Bonds: Electronegativity difference ≥ 0.5.
• Nonpolar Bonds: Electronegativity difference < 0.5.

Types of Covalent Bonds

• Nonpolar Covalent Bonds: Equal sharing (e.g., H₂)
• Polar Covalent Bonds: Unequal sharing (e.g., HF)
• Ionic Bonds: Transfer of electrons (e.g., NaCl)

Organic Compounds and Hydrocarbons

• Alkanes: Saturated compounds, formula CₙH₂ₙ₊₂
• Alkenes: Contain at least one double bond (e.g., C₂H₄)
• Alkynes: Contain at least one triple bond (e.g., C₂H₂)

Bond Length and Strength

• Single Bonds: Longest, weakest (e.g., C-C)
• Double Bonds: Shorter, stronger than single
• Triple Bonds: Shortest, strongest

Sigma and Pi Bonds

• Single Bond: 1 sigma
• Double Bond: 1 sigma, 1 pi
• Triple Bond: 1 sigma, 2 pi
• Sigma Bonds: Stronger than pi bonds

Hybridization

• sp³: Carbon with 4 single bonds
• sp²: Carbon with a double bond
• sp: Carbon with a triple bond

Formal Charge Calculation

• Formula: Valence electrons - (bonds + dots)
• Examples include calculating charges for sulfur and nitrogen.

Functional Groups

• Alcohols (e.g., CH₃CH₂OH): OH group, suffix '-ol'
• Aldehydes (e.g., CH₃CHO): Carbonyl group at chain end, suffix '-al'
• Ketones: Carbonyl group in middle of chain, suffix '-one'
• Ethers: Oxygen between two carbon atoms
• Esters: Contain a carbonyl group adjacent to an oxygen
• Carboxylic Acids: Contain carbonyl and hydroxyl group, suffix '-oic acid'

Expanding Condensed Structures

• Practice converting condensed formulas into expanded Lewis structures.

Tips and Additional Concepts

• Bonding Electrons: Count of bonded pairs
• Nonbonding Electrons: Count of lone pairs
• Hybridization of Bonds: Determined by hybridization of bonded atoms

Resources

• For more detailed study, refer to additional online resources or playlists specifically focusing on organic chemistry topics.