The spacing between layers of atoms in KCl crystal is 3.1 × 10-10 m. A beam of X-rays is constructively scattered in first order from the surface of the crystal at an angle of 2.9°. The wavelength of X-rays is ______ (sin 2.9° = 0.0506)

The spacing between layers of atoms in KCl crystal is 3.1 × 10-10 m.

1.	The spacing between layers of atoms in KCl crystal is 3.1 × 10-10 m. A beam of X-rays is constructively scattered in first order from the surface of the crystal at an angle of 2.9°. The wavelength of X-rays is ______ (sin 2.9° = 0.0506)
A.	1.32 × 10-11 m
B.	3.71 × 10-11 m
C.	4.24 × 10-11 m
D.	3.14 × 10-11 m
Answer» E.