Question

X-rays are used in determining the molecular structure of crystals because:

• A. It's energy is high
• B. It can penetrate the material
• C. It's wavelength is comparable to interatomic distance
• D. It's frequency is low

Answer 1

The correct option is C It's wavelength is comparable to interatomic distance

Crystal structure is explored through the diffraction of waves having a wavelength comparable to the interatomic spacing - in crystals. Radiation of longer wavelength cannot resolve the details of structure while radiation of much shorter wavelength is diffracted through inconveniently small angles.

So, X-rays are used, whose wavelength is comparable to interatomic distance.

Hence, option C is correct.