Chapter 4-Organic Compounds

Understanding Covalent Bonds

• Electron Dot Structure: Shows valence electrons.

  • Example: H:H (for H2)

• Lewis Structure: Depicts covalent bonding.

  • Example: H-C-C-C-H (for propane)

Drawing Structural Formulas

Steps to Draw

1. Identify Element Valence:

   • Hydrogen: 1

   • Carbon: 4

   • Nitrogen: 3

   • Oxygen: 2

   • Halogens: 1

2. Types of Structural Formulas

• Condensed Structural Formula: Simplifies atom attachment without depicting covalent bonds explicitly.

• Skeletal Structures: Represent covalent bonds with lines; carbon atoms are represented only if necessary.

Polar Covalent Bonds

Key Concepts

• Electronegativity: An atom’s ability to attract electrons.

• Differences in electronegativity lead to unequal sharing of electrons, forming polar bonds.

• Bond Types:

  • Nonpolar Covalent: Equal sharing

  • Polar Covalent: Unequal sharing leading to partial charges.

Determining Bond Polarities

• A polar bond typically forms between hydrogen/carbons and nitrogen, oxygen, fluorine, or chlorine.

• Molecules can be polar if they contain polar bonds and have an asymmetrical shape.

Types of Noncovalent Interactions

1. Permanent Charge Interactions:

   • Hydrogen bonds

   • Dipole-dipole interactions

2. Temporary Charge Interactions:

   • London forces

Organic Compound Families

Organic Compound Classifications

• Hydrocarbons: Contain only carbon and hydrogen, utilizing London forces.

Families with Functional Groups

• Single Bonds with Oxygen:

  • Alcohols, Phenols, Ethers

• Bonds with Sulfur:

  • Thiols, Sulfides, Disulfides

• Bonds with Nitrogen:

  • Amines

• Bonds with Halogens:

  • Alkyl halides

Carbonyl Compounds

• Carbonyl Group: C=O bond's significance in:

  • Ketones (attached to two carbon atoms)

  • Aldehydes (attached to at least one hydrogen)

• Carboxylic Acids and Esters: Variants of carbonyls combining C=O and other groups.