Question

Give one example of amorphous substance.

Answer 1

Hint: We should know that amorphous solid is a solid that lacks an ordered internal structure. These structures do not exhibit crystalline structure. So, to answer this question we should identify the material that lacks crystalline structure.

Step by step answer:
We should know about amorphous materials. We know that there are two types of solid amorphous and crystalline. We should note that an amorphous substance is a type of non-crystalline solid in which the atoms and molecules are not organized in a definite lattice pattern. We should remember that amorphous solids are compounds without long range order. So, as we know that amorphous solids lack three-dimensional long-range order of a crystalline material, that’s why they possess a more random arrangement of molecules, exhibit short-range order. We can also remember amorphous solid from the name of supercooled liquid because their molecules are arranged in a random manner somewhat as in liquid state.

We should know about some properties of amorphous materials.
No sharp melting point: We should remember that amorphous solid does not have a sharp melting, but if we try to melt amorphous solids it will melt in a range of temperatures. We can understand this by one example such as if we melt glass, on heating it will first soften and then melts over a temperature range. Glass, therefore, can be moulded or blown into various shapes.
Conversion into crystalline form: We can convert amorphous solid into crystalline. When we heat amorphous solid and then cooled, it becomes crystalline at some temperature. That is why glass objects of ancient time look milky because of some crystallization having taken place.
Now, one example of an amorphous substance that we should discuss is glass. As we know that glass is a transparent amorphous solid. We should know that the silicate glasses are made from chemical compound silica (silicon dioxide, or quartz) the primary constituent of sand.
If we observe the structure of glass at microscopic level, we will observe that glass has characteristics of supercooled liquids. We should know that the atomic structure of a glass lacks the long-range periodicity. We form glass by rapid cooling that is quenching the molten form. When glass is made, the material (often containing silica) is quickly cooled from its liquid state but does not solidify when its temperature drops below its melting point. At this stage, we can say the material is a super cooled liquid, an intermediate state between liquid and glass. If we want to make it amorphous solid, the material is cooled further, below the glass-transition temperature. Past this point, the molecular movement of the material's atoms has slowed to nearly a stop and the material is now a glass. This new structure is not as organized as a crystal, because it did not freeze, but it is more organized than a liquid.
So, from the above discussion we manage to answer about amorphous substances and one example of it is glass.

Note: We should know that crystalline solid is a solid material whose constituents (such as atoms, molecules, or ions) are arranged in a highly ordered microscopic structure, forming a crystal lattice that extends in all directions. Examples of large crystals include snowflakes, diamonds, and table salt. We should know that crystallization is the process of forming a crystalline structure from a fluid or from materials dissolved in a fluid. An ideal crystal has every atom in a perfect, exactly repeating pattern.