Question

Which among the following is a supercooled liquid?

• A. Diamond
• B. Graphite
• C. Copper
• D. Glass

Answer 1

The Correct Option is D

Solution:

The term supercooled liquid refers to a state of matter that retains liquid properties even below its freezing point, where it normally should form a crystalline structure. A classic example of such a material is glass.

Glass is an amorphous solid, meaning it lacks the long-range order characteristic of crystalline structures. Unlike most solids that crystallize upon cooling, glass transitions into a rigid form without forming a crystal lattice. This behavior is why glass is often referred to as a supercooled liquid. The molecules in glass are neither completely free to move as in a true liquid nor are they arranged in a periodic structure like in a crystalline solid. Instead, they are locked into a disordered, glassy state.

Let's examine each option:

• Diamond: A crystalline form of carbon with a highly ordered structure.
• Graphite: Another crystalline allotrope of carbon with layers of hexagonal planes.
• Copper: A metal that forms a crystalline lattice in solid form.
• Glass: An amorphous solid that behaves as a supercooled liquid.

Correct Answer: Glass

Answer 2

Glass is often mistakenly referred to as a supercooled liquid due to its lack of a crystalline structure, which is typical of most solids. However, this description is misleading. While glass does not have the ordered atomic arrangement found in crystalline solids, it is more accurately described as an amorphous solid. In fact, the atoms in glass are arranged randomly, much like in liquids, but the material is rigid and stable like solids. The term "supercooled liquid" originated because of the gradual transition from a liquid state to its solid form, but glass doesn't flow or change shape over time like a liquid would, which further emphasizes the differences between glass and true liquids.