Ionic & Covalent Bonds 9

Ionic bond

A chemical bond formed by the transfer of electrons from a metal to a nonmetal.

Ionic bonding ions

Metals lose electrons to form cations (+), nonmetals gain electrons to form anions (-).

Electrostatic attraction

The force that holds ionic bonds together between oppositely charged ions.

Example of an ionic compound

NaCl (Sodium chloride).

General properties of ionic compounds

High melting and boiling points, solid at room temperature, brittle, conduct electricity when molten or dissolved in water.

Covalent bond

A chemical bond formed by the sharing of electrons between two nonmetals.

What is formed in covalent bonding?

Molecules.

Types of covalent bonds

Single bond (1 pair shared), double bond (2 pairs), triple bond (3 pairs).

Examples of covalent molecules

H₂ (single), O₂ (double), N₂ (triple), H₂O (polar covalent).

General properties of covalent compounds

Low melting and boiling points, poor conductors of heat and electricity, can exist as gases, liquids, or soft solids.

Ionic bonding elements

Usually occurs between metals and nonmetals.

Covalent bonding elements

Usually occurs between two nonmetals.

Electron behavior in ionic bonds

Ionic → electron transfer.

Electron behavior in covalent bonds

Covalent → electron sharing.

Crystal lattice formation

Ionic compounds form crystal lattices.

Discrete molecules formation

Covalent compounds form discrete molecules.