Question

Molybdenum (Mo) has a BCC crystal structure, an atomic radius of 0.1363 nm, and an atomic weight of 95.94 g/mol. Compute and compare its theoretical density with the experimental value found inside the front cover of the book.

Answer 1

Answer:

Solid State or Condense matter book

Explanation:

Answer 2

Answer

The answer is 10.78 g/cm experimentally

Explanation:

Density = $\frac{mass}{volume}$

We see that there BCC structure of Mo has 9 atoms, and the edge length of the cell (a) is twice the atomic radius (

r).

a = 9, r = 0.1363 nm = 1.363 A

∴ a = 2 × 9 r = 18r

Effective volume of atoms = $a^{3}$ =$(18r)^{3} = 5832(1.363)^{3}$= 14, 767.434 $cm^{3}$

molar mass of Mo = 95.95 g/mol

∴Density = $\frac{95.95 g/mol}{14, 767.4355 cm^{3} }$ × $\frac{1 mol}{6.022*10^{23} atoms Mo }$

= 1.0788 × $10^{20}$ = 10.79 E18

= 10.79 g/cm3 (experimental density)

Theoretical density= 10. 22 g/cm3