Which of the steps is not needed to determine whether the Bragg condition is fulfilled? O All of these steps are necessary O Calculate their respective interplanar distances O Calculate the angle 0 for all the set of lattice planes O Index all the set of lattice planes that can fulfill the condition O Determine whether the Bragg condition is fulfilled knowing the wavelength of X-rays

The vanadium crystallizes in the body centered cubic lattice with a lattice parameter a. The X-ray diffraction data were collected from this compound and the following first four Bragg positions 20 (degrees): 21.06, 30.17, 37.03 and 43.10 were registered. The wavelength of the used X-ray radiation is 2 = 1.54Á. 1- Give the Bragg's Law. 2- Determine the inter-planer spacing d of the family of lattice planes (hke) of the cubic system. hkt 3 - Using the structure factor, determine the allowed reflections of the body centered cubic. 4- Index the four Bragg angles given above and calculate the cell parameter a.