Chemistry - Solid State Question with Solution | TestHub

Number of particles in $0.4$ mol of the compound is $N=0.4\times N_A$.

$N=0.4\times 6.022\times 10^{23}=2.4088\times 10^{23}$

In a close-packed structure, if the number of particles is $N$, the number of octahedral voids is $N$ and the number of tetrahedral voids is $2N$.

Total number of voids $=N+2N=3N$

Total number of voids $=3\times 2.4088\times 10^{23}=7.2264\times 10^{23}$

Answer: $7.2264\times 10^{23}$