substance beta ceriom is fourd to crystallze in a cabic latt

substance beta ceriom is fourd to crystallze in a cabic lattice, with an edge length of unit cell? $12.0 pm If the density of solid beta cerim ix 6.934 g/m, how may Ce atos ape these pr Your answer should be an integer adoms Subil Answer Retry Entire Group 9 more group attempts remaining Preious

Solution

1) Calculate the average mass of one atom :

140.116 g mol¯¹ ÷ 6.022 x 10²³ atoms mol¯¹ = 23.267 x 10¯²³ g/atom

2) Determine atoms in 1 cm³:

6.934 / 23.267 x 10¯²³ = 0.2980 x 10²³ atoms in 1 cm³

3) Determine volume of the unit cell:

(5.12 x 10¯⁸ cm)³ = 134.21 x 10¯²⁴ cm³

4) Determine number of unit cells in 1 cm³:

1 cm³ / 134.21 x 10¯²⁴ cm³ = 0.0074 x 10²⁴ unit cells

5) Determine atoms per unit cell:

0.2980 x 10²³ atoms / 0.0074 x 10²⁴ unit cells = 4 atoms per unit cell