A diffraction grating with a width of 2.1 cm contains 1050 lines/cm across that width. For an incident wavelength of 610 nm, what is the smallest wavelength difference this grating can resolve in the second order? Number i Units Calculate the minimum number of lines needed in a grating that will resolve a doublet of 483.8 and 484.6 nm in the second-order spectrum. Number i Units Na+ CI- do do Consider a two-dimensional square crystal structure, such as on side of the structure shown in the figure. The largest interplanar spacing of reflecting planes is the unit cell size ao. (a) Determine the second largest interplanar spacing. 2nd (b) Determine the third largest interplanar spacing. 3rd = (c) Determine the fourth largest interplanar spacing. 4th = (d) Determine the fifth largest interplanar spacing. 5th (e) Determine the sixth largest interplanar spacing. 6th