The Solid State

Question 225

What other element may be added to silicon to make electrons available for the conduction of electric current?


When doping a semiconductor, such as the group IV element silicon (Si), with arsenic (As), a pentavalent n-type dopant from group V in the periodic table the dopant behaves as an electron donor.

Question 226

Why does Frenkel defect not change the density of AgCl crystal?

In the frenkel defect the ions are not removed from the crystal to maintain electrical neutrality. so there will be no change in the crystal structure. that is there is no decrease in the no of ions.all the ions are inside the crystal.they are only dislocated.
Question 227

What is the difference between ferromagnetic and ferrimagnetic substances?


In ferromagnetic materials, neighboring dipoles tend to line up in the same direction, whereas in ferrimagnetic materials, neighboring dipoles tend to line up in opposing directions.

Question 228

Which ‘point defect’ lowers the density of ionic crystals?


Schottky Defect lowers the density of ionic crystal.

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