Question

An element occurs in bcc structure with a cell edge of 288pm.the density of metal is 7.2g/cm^3.how many atoms does 208g of the element contain?

Answer 1

I think it is cesium chloride

Answer 2

${\huge{\underline{\underline{\mathcal{\red{♡ANSWER♡}}}}}}$.

• ❤.. ${Volume of the unit cell}$=${(288pm)^3}$
• ❤..=${(288×10^-12 m)^-3 = (288×10^-10 cm)^3}$
• ❤..=${2.39×10^-23 cm^3}$
• ❤..${Volume of208 g of element}$
• ❤..$\frac{mass}{density}$=$\frac{208g}{7.2gcm^-3}$=${28.88cm^3}$
• ❤..${Number of unit cells in this volume}$

=$\frac{28.88cm^3}{2.39×10^-23Cm^3/unit cell}$=${12.08×10^23 unit cells}$

• ⭐.. Since each${bcc}$cubic unit cell contains ${2}$ atoms,therefore,the total number of atoms in ${208g = 2}$${(atoms/unit cell)×12.08×10^23}$ unit cells=${24.16×10^23}$ atoms.