Under which situations can an amorphous substance change to crystaline form?

Explanation

To determine the situations under which an amorphous substance can change to a crystalline form, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Amorphous and Crystalline Substances:**
- Amorphous substances lack a well-defined geometric structure and have a disordered arrangement of atoms or molecules.
- Crystalline substances, on the other hand, have a highly ordered structure with a repeating pattern.

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