AP EAMCET201923 Apr 2019Morning ShiftChemistryp Block Elements (Group 13 & 14)Actual
Which of the following statements are not correct? (A) Diode is a combination of (n )-type and p-type semiconductors. (B) Silicon or germanium is electron rich impurity. (C) Phosphorus and arsenic are electron deficient impurities. (D) Schottky defect decreases the density of the crystal.
Options
- AB, C
- BA, D
- CC, D
- DA, C
Correct answer
A. B, C
Step-by-step solution
Among the given statements, (B) and (C) are incorrect. Their correct explanations are as follows: (B) Silicon or germanium belong to group 14, so they can be used as semiconductors. (C) Phosphorus and arsenic belong to group 15, so they have 5 valence electrons. Out of 5 electrons, 4 are used in covalent bonding with Si. The 5th electron is extra and hence become delocalised. Thus, they are electron rich impurities.