Calculate the distance between two parallel $(220)$ planes in a crystal with an edge length of $450 \, pm$. (in $pm$)

Lithium forms a body-centred cubic $(BCC)$ structure. The length of the side of its unit cell is $351 \ pm$. The atomic radius of lithium will be: ............. $pm$

Calculate the number of atoms in $1 \ g$ of a metal if it forms an $fcc$ crystal structure,given that $\varrho \times a^3 = 1.728 \times 10^{-22} \ g$.

In an orthorhombic crystal system,the values of $a$,$b$,and $c$ are $4.2 \, \mathring{A}$,$8.6 \, \mathring{A}$,and $8.3 \, \mathring{A}$ respectively. Given the molar mass of the solute is $155 \, g \, mol^{-1}$ and the density is $3.3 \, g \, cm^{-3}$,calculate the number of formula units $(Z)$ per unit cell.

To obtain a diffraction peak for a crystalline solid with interplane distance equal to the wavelength of incident $X$-ray radiation,the angle of incidence should be $....\,^{\circ}$

An element with $BCC$ structure has an edge length of $500 \ pm$. If its density is $4 \ g \ cm^{-3}$, find the atomic mass of the element.