What are the number of octahedral and tetrahedral voids in 0.3 mole substance respectively if it forms hcp…
What are the number of octahedral and tetrahedral voids in 0.3 mole substance respectively if it forms hcp structure?
$1.8066 \times 10^{23}$ and $3.6132 \times 10^{23}$
$3.6132 \times 10^{23}$ and $1.8066 \times 10^{23}$
$6.022 \times 10^{23}$ and $12.044 \times 10^{23}$
$12.044 \times 10^{23}$ and $6.022 \times 10^{23}$
Solution
Number of atoms in $0.3 \mathrm{~mol}$
$\begin{aligned}
& =0.3 \times \mathrm{N}_{\mathrm{A}} \\
& =0.3 \times 6.022 \times 10^{23} \\
& =1.8066 \times 10^{23}
\end{aligned}$
i. For hep structure, Number of octahedral voids
$=$ Number of atoms
$=1.8066 \times 10^{23}$
ii. For hcp structure, Number of tetrahedral voids
$\begin{aligned}
& =2 \times \text { Number of atoms } \\
& =2 \times 1.8066 \times 10^{23} \\
& =3.6132 \times 10^{23}
\end{aligned}$