Voids in crystal lattice

The distance between an octahedral and a tetrahedral void in $\mathrm{pm}$ in FCC lattice would be: 

(Consider edge length is $7 \mathrm{pm}$)

Right option for the number of tetrahedral and octahedral voids in hexagonal primitive unit cell are:

In a compound, atoms of element $\mathrm{Y}$ form cubic close packing lattice and those of element $\mathrm{X}$ occupy$\frac{2}{3} \mathrm{times}$  of tetrahedral voids. The formula of the compound will be

A solid compound $\mathrm{XY}$ has $\mathrm{NaCl}$ structure. If the radius of the cation is $100 \mathrm{pm}$, the radius of the anion $\left({\mathrm{Y}}^{-}\right)$ in pm will be

(Round of the answer up to four significant figures)

The total number of tetrahedral voids in the face centred unit cell is

In a carbon allotrope having $\mathrm{FCC}$ lattice, two atoms are at $\left(0, 0, 0\right)$ and $\left(\frac{\mathrm{a}}{8}, \frac{\mathrm{a}}{8}, \frac{\mathrm{a}}{8}\right)$ coordinates. What is the ratio of $\mathrm{C}-\mathrm{C}$ bond length distance to the edge length of the unit cell?

 In a compound, oxide ions are arranged in cubic close packing arrangement. Cations $\mathrm{A}$ occupy $1/6$ of the tetrahedral voids and cations $\mathrm{B}$ occupy $1/3$ of the octahedral voids. The formula of the compound is
 

For the structure given below the site marked as S is a :-

The radius of ${\mathrm{Ag}}^{+}$ ion is $126 \mathrm{pm}$ and ${\mathrm{I}}^{-}$ ion is $216 \mathrm{pm}$. The co-ordination number of ${\mathrm{Ag}}^{+}$ ion is:-

Which type of structure does $\mathrm{RbCl}$ have if ionic radii of ${\mathrm{Rb}}^{\oplus }$ and ${\mathrm{I}}^{\Theta }$ respectively are $1.46 \stackrel{°}{\mathrm{A}}$ and $2.16 \stackrel{°}{\mathrm{A}}$:-

An ionic compound is expected to have a tetrahedral structure if ${\mathrm{r}}_{+}/{\mathrm{r}}_{-}$ lies in the range of

The total number of tetrahedral voids in the face-centred unit cell is _____.

An ionic crystal lattice has ${\mathrm{r}}^{+}/{\mathrm{r}}^{-}$ radius ratio of $0.524$. Its coordination number is

The number of tetrahedral sites per sphere in ccp structure is,

The number of octahedral sites per sphere in fcc structure is

The ratio of close packed atoms to octahedral holes in hexagonal close packing is

The ratio of close packed atoms to tetrahedral holes in cubic packing is

The number of tetrahedral and octahedral holes in a hexagonal primitive unit cell are: 

The range of radius ratio $\left({\mathrm{r}}^{+}/{\mathrm{r}}^{-}\right)$ for an octahedral arrangement of ions in an ionic solid is

$\mathrm{KCl}$ crystallises in the same type of lattice as does $\mathrm{NaCl}$. Given that, ${\mathrm{r}}_{{\mathrm{Na}}^{+}}/{\mathrm{r}}_{{\mathrm{Cl}}^{-}}=0.55$ and ${\mathrm{r}}_{{\mathrm{K}}^{+}}/{\mathrm{r}}_{{\mathrm{Cl}}^{-}}=0.74$.

Calculate the ratio of the side of the unit cell of $\mathrm{KCI}$ to that of $\mathrm{NaCl}$.