The remainder on dividing $5^{99}$ by 11 is ____________.

The distance between Na⁺ and Cl^$-$ ions in solid NaCl of density 43.1 g cm^$-$3 is _______________ $\times$ 10^$-$10 m. (Nearest Integer)

Number of crystal systems from the following where body centred unit cell can be found, is ____________.

Cubic, tetragonal, orthorhombic, hexagonal, rhombohedral, monoclinic, triclinic

An atomic substance A of molar mass $12 \mathrm{~g} \mathrm{~mol}^{-1}$ has a cubic crystal structure with edge length of $300 ~\mathrm{pm}$. The no. of atoms present in one unit cell of is ____________. (Nearest integer)

Sodium metal crystallizes in a body centred cubic lattice with unit cell edge length of $4~\mathop A\limits^o$. The radius of sodium atom is __________ $\times ~10^{-1}$ (Nearest integer)

A metal M crystallizes into two lattices :- face centred cubic (fcc) and body centred cubic (bcc) with unit cell edge length of $2.0$ and $2.5\,\mathop A\limits^o$ respectively. The ratio of densities of lattices fcc to bcc for the metal M is ____________. (Nearest integer)

Atoms of element X form hcp lattice and those of element Y occupy ${2 \over 3}$ of its tetrahedral voids. The percentage of element X in the lattice is ____________. (Nearest integer)

An element M crystallises in a body centred cubic unit cell with a cell edge of $300 \,\mathrm{pm}$. The density of the element is $6.0 \mathrm{~g} \mathrm{~cm}^{-3}$. The number of atoms present in of the element is ____________ . (Nearest integer)