Question

what is the difference between structure of nacl and kcl

Answer 1

there is no difference bw structures of both of them
the both are purely ionic in nature and thus exist as ions

Answer 2

Answer

NaCl has a cubic unit cell. It is best thought of as a face-centered cubic array of anions with an interpenetrating fcc cation lattice (or vice-versa). The cell looks the same whether you start with anions or cations on the corners. Each ion is 6-coordinate and has a local octahedral geometry.

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