Request a call back

Join NOW to get access to exclusive study material for best results

JEE Class main Answered

  Question: in a crystalline solid of XY3 cubic closed packed arrangement for its element Y,,,, X occupies.... ? Answer: 33% OCTAHEDRAL VOIDS.  how was this worked out? not the math necessarily,, but the voids occupied by X being OCTAHEDRAL and not TETRAHEDRAL. i don’t understand this part. i’d really appreciate it if someone could walk me through the logic here. thanks.
Asked by astutijoshi | 03 Jun, 2019, 17:12: PM
answered-by-expert Expert Answer
Given:
 
XY3 has CCP arrangement for element Y.
 
atoms in one unit cell of CCP = 4
 
No. of atoms of X = 4/3
 
No. of octahedral voids = 4
 
So, % of octahedral voids filled 
 
equals space fraction numerator begin display style bevelled 4 over 3 end style over denominator 4 end fraction cross times 100

space equals space 33 percent sign
 
The number of octahedral voids present in lattice is the same as the number of  close- packed particles,
whereas, the number of tetrahedral voids is the twise of that number.
 
Therfore the total number of octahedral voids is 4 and tetrahedral voids is 8 per unit cell.
 
 
Answered by Varsha | 04 Jun, 2019, 11:21: AM