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The longest wavelength that can be analy...

The longest wavelength that can be analysed by a sodium chloride crystal of spacing `d = 2.82 Å` in the second order is -

A

`2.82 Å`

B

`5.64 Å`

C

`8.46 Å`

D

`11.28 Å`

Text Solution

Verified by Experts

The correct Answer is:
A
Bragg’s X-ray diffraction law
`nlamda = 2d sin theta`
`implies lamda = (2d sin theta)/(n)`
For largest `lamda` take `sin theta =1`
Hence, `lamda=(2xx2.82(Å))/(2)=2.82 Å" "["as "n =2 ]`
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