Amorphous solids lack a lattice or crystalline structure and make up only 10% of solids. Glass is the best-known example. Molecules in solids are bound together with no freedom of movement, but still wobble in their bonds. Crystalline solids have an orderly pattern, while amorphous solids may have a repeating pattern for small portions. Amorphous solids can be natural or man-made, and can consist of crystalline solids. They are sometimes called supercooled liquids and do not immediately liquefy when exposed to heat.
An amorphous solid is any material that does not have its molecules arranged in a lattice or crystalline structure. Amorphous solids are relatively rare, making up only 10% of solids in the world. The best known example of an amorphous solid is glass, and indeed these solids are sometimes generally called glasses.
The three states of matter – solid, liquid and gaseous – occur due to the different degrees of motion of the molecules that make up the substances. Molecules and atoms in gases have a large range of motion, spreading out because the molecules are loosely bound to each other. Liquids have a narrower range of motion, yet their molecules still move freely within those boundaries, changing position. This freedom is what gives liquids their permanent shapelessness.
Molecules in solids, on the other hand, are bound together with no real freedom of movement. The molecules still move, however, wobbling in their bonds. The rocking motion is what allows solids to heat up. The faster the molecules stir in their bonds, the hotter the object becomes.
In crystalline solids, which make up 90% of the world’s solids, molecules are linked in an orderly pattern. This ordered pattern repeats exactly throughout the structure, creating a lattice of molecules. Conversely, an amorphous solid may have a repeating pattern for small portions of its composition, but not for its entirety.
Amorphous solids can be natural or man-made products. Sand striking a lightning bolt will naturally cause glass to form at the point of impact. Commercial glass, however, is man-made, using a process that creates the same conditions as lightning, but in a controlled environment. Besides glass, one of the most widely used amorphous solids is plastic. Plastic is made up of polymers, long strings of molecules deliberately chained together.
Also, amorphous solids can consist of crystalline solids. For example, glass is made from quartz sand, a crystalline solid. The sand is heated to extreme temperatures, which cause it to melt effectively, and then rapidly cooled, or supercooled, so the molecules don’t have time to rearrange themselves into a lattice shape. This supercooling results in a molecular arrangement of the glass similar to someone taking a snapshot of the liquid.
Because the structures of amorphous solids appear similar to liquids, they are sometimes called supercooled liquids. This similarity is also why the myth has developed that glass is actually a slow-moving liquid. Also, unlike a crystalline solid, an amorphous solid does not immediately liquefy when exposed to heat, but becomes softer and softer.
Protect your devices with Threat Protection by NordVPN
