Question

lithium metal has a body centerd cubic unit cell.what is the number of lithium atoms par unit cell​

Answer 1

Answer:

Density of unit cell is given as

Density−

MA×Volumeofunitcell

no.ofatomperunitcell×Molarmassofatom

In BCC structure

at corner =

8

1

×8=1

at Body centre+1=1atom

Total atom in BCC =2atom

Molar mass of lithium =6.94

Given density =0.53gcm

−3

On putting all values we have

0.53gcm

−3

=

6.022×10

23

mol

−1

×0.53gcm

−3

2×6.94

V=4.34×10

23

cm

3

V=4.34×10

−23

ml

Thus volume of unit cell is 4.34×10

−23

cm

3