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Grade 12Physical Chemistry

What is X-ray density and what is pyknometric density? If the former is 2.178 and latter is 2.165, then what is the fraction of sites unoccupied in the lattice? (Q: from Solid State)

Profile image of Paras Goel
12 Years agoGrade 12
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1 Answer

Profile image of Sunil Kumar FP
11 Years ago
pyknometric density:-Pycnometric density is the closest approximation to true density calculated from the molecular weight and crystalline lattice of a substance.
First density = 2.165 * 10 ^3
Difference of density = 2178-2165 = 13 kg/m 3
Therefore,
fraction of unoccupied site = 13/2178 = 5.96 * 10 -3