Calculate the volume of the unit cell of an element with a density of $7.2 \ g \ cm^{-3}$ that forms a $bcc$ structure. ($288 \ g$ of this element contains $3.35 \times 10^{24}$ atoms).

The only $INCORRECT$ statement for cubic metallic crystal is

Silver (atomic weight $= 108 \ g \ mol^{-1}$) has a density of $10.5 \ g \ cm^{-3}$. The number of silver atoms on a surface of area $10^{-12} \ m^2$ can be expressed in scientific notation as $y \times 10^x$. The value of $x$ is

Select the correct statement.

Silver has an atomic radius of $144 \ pm$ and the density of silver is $10.6 \ g \ cm^{-3}$. Based on this information, identify the correct statement.

$CCP$ lattice of a solid made up of $B^{-}$ ions has an edge length of $3 \ \mathring{A}$ and a density of $5 \ g/cm^3$. If in this lattice $A^{+}$ ions are placed at alternate tetrahedral voids,then the percentage increase in density will be $............. \ \%$. [Molar mass of $A^{+} = 30 \ g/mol$,$N_A = 6 \times 10^{23}$]