Crystalline solids are characterised by:
AA short-range ordered arrangement of particles
BA long-range, regularly repeating arrangement of particles
CNo definite shape
DThe absence of definite melting point
Answer & Solution
Correct answer: B. A long-range, regularly repeating arrangement of particles
Crystalline solids have a long-range, periodic arrangement of constituent particles. NaCl, diamond, ice, metals at usual conditions are crystalline.
Amorphous solids (glass, rubber) lack long-range order. They show only short-range order (option A), no definite melting point, and fracture along irregular surfaces.
Crystallinity is what gives sharp X-ray diffraction patterns and well-defined melting points.
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