An element with density `11.2 g cm^(-3)` forms a fcc lattice with edge length of `4 xx 10^(-8)` cm. Calculate the atomic mass of the element. `[Given : N_(A) = 6.022 xx 10^(23)"atoms " mol^(-1)]`

Explanation

Use the relation
`d=(zM)/(a^(3)N_(A)) or M=(da^(3)N_(A))/(z)`
Here, z = 4 (for fcc crystal), `d=11.2" g cm"^(-3) and a=4xx10^(-8)cm`
Substituting the values in the above equation, we have
`M=(11.2xx(4xx10^(-8))^(3)xx6.022xx10^(23))/(4)=(11.2xx64xx10^(-24)xx6.022xx10^(-23))/(4)`
`=(11.2xx64xx6.022)/(4xx10)=107.9u`