Consider a homogeneous gallium arsenide semiconductor at T 300 K with Nd 1016 cm3 and Na 0. (a) Calculate the thermal-equilibrium values of electron and hole concentrations. (b) For an applied E-fi eld of 10 V/cm, calculate the drift current density. (c) Repeat parts (a) and (b) if Nd 0 and Na 1016 cm3 .

a) The electron carrier concentration is

   The hole carrier concentration is

b) The drift current density is given as

c) Repeated part a the electron carrier concentration is

  Repeated part a the holes carrier concentration is

  Repeated part b the electron density is

Explanation:

The explanation is shown on the first , second ,third and fourth image

answer: c. the experiment shows that the red substance experienced a chemical change.

explanation: chemical change is the change in which chemical composition of the substance changes. physical change is the change in which there is no change in chemical composition.

chemical changes are accompanied by following changes:

a) precipitate formation

b) energy is released or absorbed

c) formation of bubbles

d) change in color

as it is given that the red color has disappeared and there is production of gas, it means the red substance has undergone a chemical change.

e