Question

Assertion (A) : In $CsCl$ crystal, the coordination number of $C{s}^{\oplus }$ ion is $8$.
Reason (R) : $C{l}^{\ominus }$ ions in $CsCl$ adopt bcc type of packing.

• A. Both (A) and (R) are correct and (R) is the correct explanation of (A)
• B. Both (A) and (R) are correct but (R) is not the correct explanation of (A)
• C. (A) is correct but (R) is incorrect
• D. (A) is incorrect but (R) is correct
• E. Both (A) and (R) are incorrect

Answer 1

The correct option is A Both (A) and (R) are correct and (R) is the correct explanation of (A)

Limiting radius ratio = r/R	Coordination Number of cation	Structural Arrangement (Geometry of voids)	Example
0.155-0.225 0.225-0.414 0.414-0.732 0.414-0.732 0.732-1.000	3 4 4 6 8	Plane Trigonal Tetrahedral Square planar Octahedral Cubic	Boron Oxide $ZnS,Si{O}_2$ - $NaCI,Mg{O}_2$ $CsCI$