Question

39:X rays of wavelength 1.5 A incident on NaCl
crystal having a glancing spacing of 2.8 A. what is the
highest order that the Crystal can diffract?
2509585040
2.73
1.73
4.73
3.73​

Answer 1

Answer:

2.73 answer ha ye k dine hiiii kuch

Answer 2

Answer:

The highest order that $NaCl$ crystal can diffract, n, measured is $3.73$.

Therefore, option d) $3.73$ is correct.

Explanation:

Given,

The wavelength of the X-ray, λ = $1.5\AA$

The glancing spacing in the $NaCl$ crystal, d = $2.8\AA$

The highest order that $NaCl$ crystal can diffract, n =?

Now,

• From the Bragg's law;
• $2dsin\theta = n\lambda$

Here, θ is the angle of diffraction,

As we know, sinθ cannot exceed 1.

Therefore, for the highest order that crystal can diffract, the maximum value of sinθ is to be 1.

Thus,

• $2d= n\lambda$
• n = $\frac{2d}{\lambda}$
• n = $\frac{2\times 2.8}{1.5}$
• n = $3.73$

Hence, the highest order that $NaCl$ crystal can diffract, n = $3.73$.