Question

The unit cube length of LiCl (NaCl structure) is 5.14 Å. Assuming anion-anion contacts, what is the radius of chloride ion?






A)
1.24 Å




B)
1.81 Å




C)
2.97 Å




D)
4.85 Å




0% got it right! Answer: B Solution:
Inter-ionic distance of LiCl = 5.14/2 = 2.57 Å



Therefore,



The correct answer is B.

why have we taken the lengthof BC as half of the edge length?
why can't it be equal to edge length only?
plz explain.

Answer 1

it's based on the arrangement
just imagine a crystal of this kind,now measuring the length you will have two anions and a cation so now you get like the diameter so dividing by two gives you the precise measurement