Which of the following is a characteristic of amorphous solids?

Gradual softening over a range of temperatures

The correct answer is option 4. Gradual softening over a range of temperatures.

The characteristic of amorphous solids is Gradual softening over a range of temperatures.

Unlike crystalline solids, amorphous solids lack a well-defined and repeating atomic structure. As a result, they do not have a sharp and characteristic melting point. Instead, amorphous solids undergo a gradual softening over a range of temperatures when heated. This is because their molecular arrangement is more random, leading to a less organized and defined transition from solid to liquid compared to crystalline solids.