Question

6. (i) Define Schottky defect.

(ii) Copper crystallizes into a fcc lattice with edge length
$3.61 \times 10 {}^{ - 8} cm$
Calculate the density of copper.(Atomic mass of copper = 63.5g/mol).​

Answer 1

Answer:

Copper crystallizes into a fcc lattice with edge length 3.61×10

−8

cm.

Fcc unit cell has 4 atoms per unit cell.

Cu has atomic mass of 63.5 g/mol.

Avogadro's number is 6.023×10

23

.

The calculated density is as below:

D=

a

3

N

0

​

ZM

​

=

(3.61×10

−8

)

3

×6.022×10

23

4×63.5

​

=8.97g cm

−3

This is close enough to the measured value of 8.92 g cm

−3

.

Explanation: