Question

In chromium chloride ${(CrCl_{3}), Cl^{-}}$ ions have cubic close packed arrangement and ${Cr^{3+}}$ ions are present in the octahedral holes. The fraction of the total number of holes occupied is

• A. 44564
• B. 44567
• C. 44570
• D. 44573

Answer 1

Answer: (C)

44570

Answer 2

In $CrCl_{3}$ for every, $3Cl^{-}$ ions, there is one $Cr^{3 +}$ ion is present. Thus, if there are $3Cl^{-}$ ions are present in CCP. Number of octahedral voids = 3, and tetrahedral voids = 6 Total voids = 3+6=9 As $1 \, Cr^{3 +}$ ion is present in the octahedral void, therefore, fraction of holes occupied $=\frac{1}{9}$