Question

What are crystalline solids? Give example.

Hint:

Crystalline solids show long-range order and definite geometry, unlike amorphous solids which have random arrangement.

Answer 1

Step 1: Definition.
Crystalline solids are those solids in which the constituent particles (atoms, ions, or molecules) are arranged in a definite, orderly, and repeating pattern in three-dimensional space.
Step 2: Characteristics.
- They have a definite geometric shape.
- Sharp melting point.
- Long-range order.
- Anisotropic in nature (properties vary in different directions).
Step 3: Examples.
Sodium chloride (NaCl), Diamond, Quartz, and Ice are examples of crystalline solids.
Step 4: Explanation.
In NaCl, the arrangement of Na$^+$ and Cl$^-$ ions is highly regular, forming a cubic lattice, which is a characteristic feature of crystalline solids.