Sodium has a `bc c` structure with nearest neighbour distance of `365.9` pm. Calculate its density. (Atomic mass of sodium `= 23`)

Explanation

For the bcc structure , nearest neighbour distance (d) is related to the edge (a) as `d=sqrt3/2 a`
or `a=2/sqrt3 d =2/1.732xx365.9` =422.5 pm
For bcc structure, Z=2
For sodium , M=23 `therefore rho =(ZxxM)/(a^3xxN_0)=(2xx23 g mol^(-1))/((422.5xx10^(-10)cm)^3xx(6.02xx10^23 mol^(-1))=1.51 g//cm^3`