Question

Select the correct statement(s) :-

• A. Crystalline solids melt at fixed temperature.
• B. Particles in amorphous solids are arranged in irregular pattern.
• C. Crystalline solids have regular and definite shape.
• D. None of these.

Answer 1

Answer: (A), (B), (C)

The correct options are
A Crystalline solids melt at fixed temperature.
B Particles in amorphous solids are arranged in irregular pattern.
C Crystalline solids have regular and definite shape.

The differences between crystalline and amorphous solids are laid out in the table below:

$\begin{array}{ccc}\text{Characteristics}& \text{Crystalline Solids}& \text{Amorphous Solids}\\ \text{Melting Point}& \text{Melt at fixed temperature}& \text{Melts steadily over range of temperatures}\\ \text{Arrangement of Constituent Particles}& \text{Regular}& \text{Irregular}\\ \text{Shape}& \text{Regular and Definite Shape}& \text{Irregular Shape in Nature}\\ \text{Cleavage}& \text{When cut, two smooth and plane pieces are obtained}& \text{When cut, two surfaces of irregular shape are obtained}\end{array}$

Hence (a), (b), (c) are correct.