If the Interplanar Spacing of NaCl Is 2

Multiple Choice

If the interplanar spacing of NaCl is 2.814 × 10−¹⁰ m, what is the predicted angle at which X-rays of wavelength 0.140 nm will be diffracted in a first-order maximum?

A) 31.3°
B) 7.20°
C) 20.5°
D) 14.4°
E) 29.8°