Question

why number of octahedral voids is equalt to number of atoms

Answer 1

Octahedral void is formed when 6 spheres touching each other forming regular octahedral. thus if the triangular void of 1 hexagonal is exactly about triangular void of other hexagonal layer then the empty space between 6 such a sphere is called octahedral void . Here each sphere can create only 1 octaheral void. thus if there are N particles in the Crystal then there octaheral voids will be equals to = N.
# here each sphere is like a atom hence no. of octahedral voids is equals to no of atoms.
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