Atomic Bonding:

Matter, as we know it, exists in three general states. These three states are liquid, solid, and gas.

The atomic or molecular interactions which occur inside a substance determine its state. In this lesson, we will deal mainly along with solids since solids are of the most concern in engineering applications of materials. Gases and Liquids will be mentioned for comparative reasons only.

Solid matter is held together through forces originating among neighboring atoms or molecules. Those forces arise since of differences in the electron clouds of atoms. Alternatively, the valence electrons and those in the outer shell of atoms will determine their attraction for their neighbors. While physical attraction among molecules or atoms of a material is great then the material is held strongly together. Molecules in solids are bound strongly together. While the attractions are weaker, the substance might be in a liquid form and free to flow. The Gases exhibit virtually no attractive forces among atoms or molecules and those particles are free to move independently of every other.