[50 points] The dominant defects in Nb205 at 1000 °C are oxygen vacancies with a double positive effective charge and Nb interstitials with a double positive effective charge. These conditions apply to all of the questions below. Assume that the materials ispure. Write an equation for the formation of doubly charged oxygen vacancies inNb205. Write an equation for the formation of doubly charged Nb interstitials in Nb205.[please write the reaction so that a single interstitial defect is formed with a positive 2 effective charge] Is Nb205 n-type or p-type? Write an equilibrium constant (KV) for the reaction in i). Write an equilibrium constant (Ki) for the reaction in ii). The equilibrium constants for these reactions have been measured. They are: KV= 2.4x105 (atm1/2)Determine the ratio of oxygen vacancies to Nb interstitials at 10-10 atm and at10-20 atm of 02. (T = 1000°C and k = 8.6x10-5 eV/K)exp(-4.5 (eV)/KT) Ki = 4.9x109 (atm5/4) exp(-8.7(eV)/KT) Taking the formula unit to be Nb205-x, determine x at both of these pressures(10-10 atm and 10-20 atm). Write the electroneutrality condition for the concentrations of charged defects inNh205 Write equations for the concentration of Oxygen vacancies and Nb interstitials at low partial pressure of oxygen and high partial pressure of oxygen. In the each case, assume one of the two defects is dominant to simplify the electroneutrality condition. Make a plot of log concentration v log partial pressure (in the range of 10-10 atmto 10-20 atm) of oxygen showing the concentrations of the oxygen vacancies, Nb interstitials, and electronic charge carriers. (T = 1000°C)

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50 points the dominant defects in nb205 at 1000 c are oxygen vacancies

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[50 points] The dominant defects in Nb205 at 1000 °C are oxygen vacancies with a double positive effective charge and Nb interstitials with a double positive effective charge. These conditions apply to all of the questions below. Assume that the materials ispure. Write an equation for the formation of doubly charged o