Class 12th Chemistry 2017 Set2 Delhi Board Paper Solution
An element has atomic mass 93 g mol− 1 and density 11.5 gcm− 3 . If the edge length of its unit cell is 300 pm, identify the type of unit cell.
d = 11.5 gcm− 3
edge length (a) = 300 pm
atomic mass (M) = 93 g mol− 1
d = Zm / a3 x Na
11.5 = Z x 93 / (300x10-10 cm) 3 x 6.022 x 1023
Z = 11.5 x 27x 10-24 x 6.022 x 1023 / 93
Z = 2.009 = 2
It is body centric cubic unit cell.
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