Potassium Iodide (chemical formula: KI)has a face-centered cubic structure (just like sodium chloride).If the distance between crystal planes is d = 0.353 nm and X-rays of wavelength $\lambda$ = 0.093 4 nm are used,what is the smallest angle $\theta$ at which a diffraction maximum may be obtained?
A)9.92 $\degree$
B)7.60 $\degree$
C)13.3 $\degree$
D)15.5 $\degree$
E)6.52 $\degree$

Question

Quizplus · Accepted Answer

Using Bragg's Law, nλ = 2d sin(θ), for the first order maximum (n=1), we solve for θ: sin(θ) = λ / (2d) = 0.0934 nm / (2 * 0.353 nm) = 0.1323. Therefore, θ = arcsin(0.1323) ≈ 7.60°.

Potassium Iodide (Chemical Formula: KI)has a Face-Centered Cubic Structure (Just λ\lambdaλ

Potassium Iodide (Chemical Formula: KI)has a Face-Centered Cubic Structure (Just $\lambda$