Q2) An element has an FCC crystal structure; monochromatic x-radiation having a wavelength of 0.1542 nm was used. Order of reflection is 1. Answer the following questions for 2nd peak (20 Pt) 1- Index (i.e., give h,k, and l indices) the peak:

(400)

(222)

(112)

(111)

(200)

(220)

(100)

(311)

(110)

2- If latice parameter is 0.2456 nm, find the interplanar spacing for the peak:

0.1228 nm

0.1208 nm

0.1258 nm

0.1248 nm

3- Find the radius of the element:

0.0878 nm

0.0968 nm

0.0868 nm

0.0858 nm

4- Find the diffraction angle for the the peak:

77.803

77.903

77.783

77.763