Certain ceramic materials such as those based on oxides of yttrium, barium, and copper have been shown to be superconductors near liquid nitrogen temperature (~77 to 100 K). Since ceramics are brittle, it has been proposed to make long wires of these materials by encasing them in a silver tube. In this work, researchers investigated the diffusion of oxygen in a compound YBa2Cu3O7. The data in the temperature range 500 to 650 °C are shown below for undoped (i.e., silver free) samples?
Temperature T ( ˚C)Diffusion Coefficient D (cm2/s)
500............................................2.77 × 10-6
600............................................5.2 × 10-6
650............................................9.24 × 10-6
Assume that these data are sufficient to make a straight line fit for the relationship between ln(D) and 1/T and calculate the values of the activation energy for diffusion of oxygen in YBa2Cu3O7 containing no silver.