How crystal solids are classified?write any two examples?
Solids can be divided in to two distinct classes.
1) Crystalline solids
2) Amorphous solids
CRYSTALLINE SOLIDS
Crystalline solids have the following fundamentals properties.
1. They have characteristic geometrical shape.
2. They have highly ordered three-dimensional arrangements of particles.
3. They are bounded by PLANES or FACES
4. Planes of a crystal intersect at particular angles.
5. They have sharp melting and boiling points.
Examples:
Copper Sulphate (CuSO4), NiSO4, Diamond, Graphite, NaCl, Sugar etc
AMORPHOUS SOLIDS
Solids that don’t have a definite geometrical shape are known as Amorphous Solids.
1. In these solids particles are randomly arranged in three dimension.
2. They don’t have sharp melting points.
3. Amorphous solids are formed due to sudden cooling of liquid.
4. Amorphous solids melt over a wide range of temperature
5. Examples:
Coal, Coke, Glass, Plastic, rubber etc