Assertion :X-rays are used for studying the structure of crystals. Reason: The difference between the atoms of crystals is of the order of wavelength of X-rays.
Assertion
X-rays are used for studying the structure of crystals.
Reason
The difference between the atoms of crystals is of the order of wavelength of X-rays.
Both Assertion and Reason are correct and Reason is the correct explanation for Assertion.
Crystals are regular arrays of atoms, and X-rays can be considered waves of electromagnetic radiation. ... X-rays are used to produce the diffraction pattern because their wavelength λ is typically the same order of magnitude (1–100 angstroms) as the spacing d between planes in the crystal.
Where d is the interplanar spacing, θ the angle between the wave vector of the incident plane wave, ko, and the lattice planes, λ its wavelength and n is an integer, the order of the reflection. It is equivalent to the diffraction condition in reciprocal space and to the Laue equations.