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

Using Bragg's Law, nλ = 2d sin θ, for first-order (n=1) and given values, solve for θ: sin θ = λ / (2d) = 0.140 nm / (2 * 2.814 × 10^-10 m) = 0.140 × 10^-9 m / (5.628 × 10^-10 m) ≈ 0.2487. Thus, θ ≈ 14.4°.

If the Interplanar Spacing of NaCl Is 2