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°

Question

Quizplus · Accepted Answer

The Bragg's law equation, $n\lambda = 2d\sin\theta$, where $n$ is the order of maximum (1 in this case), $\lambda$ is the wavelength of X-rays (0.140 nm), and $d$ is the interplanar spacing (2.814 × 10^-10 m), can be rearranged to solve for $\theta$. Plugging in the given values and solving for $\theta$ gives an angle close to 14.4°.

If the Interplanar Spacing of NaCl Is 2