Question

Teacher explained the stoichiometric defects in a class room. a) Explain with the help of diagrams the important differences in Schottky and Frenkel defects. (2) b) What are the consequences?​

Answer 1

Answer:

Consequences of Schottky defect

1. As the number of ions decreases as a result of this defect, the mass decreases whereas the volume remains the same. Hence density of the solid decreases

2. The crystal begins to conduct electricity to a small extent by ionic mechanism

3. The presence of too many voids lowers lattice energy and the stability of the crystal

Consequences of Frenkel defect

1. As no ions are missing from the crystal lattice as a whole, therefore density of the solid remains the same

2. The closeness of like charges tends to increases the dielectric constant of the crystal

3. The crystal conducts electricity to a small extent by ionic mechanism