Chemical Bonding Fundamentals

Chemical bonding is the force that holds atoms together in compounds. Understanding bonding is crucial for mastering chemistry.

Types of Chemical Bonds

Ionic Bonding

Ionic bonds form when electrons are transferred from one atom to another, creating ions:

• Cation: Positively charged ion (loses electrons)
• Anion: Negatively charged ion (gains electrons)
• Example: NaCl (sodium chloride)

The formation of sodium chloride:

$\text{Na} \rightarrow \text{Na}^+ + e^-$ $\text{Cl} + e^- \rightarrow \text{Cl}^-$ $\text{Na}^+ + \text{Cl}^- \rightarrow \text{NaCl}$

Covalent Bonding

Covalent bonds form when atoms share electrons:

• Single bond: One pair of shared electrons: H-H
• Double bond: Two pairs of shared electrons: O=O
• Triple bond: Three pairs of shared electrons: N≡N

Water molecule formation:

$2\text{H}_2 + \text{O}_2 \rightarrow 2\text{H}_2\text{O}$

Here's the molecular structure of water:

Ethanol molecular structure:

Metallic Bonding

Found in metals, where electrons are delocalized across a lattice of metal ions.

Bond Polarity

The electronegativity difference between atoms determines bond polarity:

• Nonpolar covalent: Equal sharing (ΔEN < 0.5)
• Polar covalent: Unequal sharing (0.5 < ΔEN < 1.7)
• Ionic: Electron transfer (ΔEN > 1.7)

Key Concepts

1. Atoms bond to achieve stable electron configurations
2. The octet rule guides bonding behavior
3. Bond strength affects molecular properties
4. VSEPR theory predicts molecular geometry

Understanding chemical bonding is essential for predicting compound properties and reactions.