Calculate the number of unit cells in 8.1 g of aluminium if it crystalliz3es in aface cented cubic (f.c.c) structure. (Atomic mass of Al= 27 `g mol^(-1) `)

Explanation

1 mole of Al ` = 27 g = 6.02 xx 10^(23) ` atoms
No, of Al atoms present in 8.1 g of Al ` = ( 6.02 xx 10^(23))/ 27 xx 8.1 = 1.806 xx 10^(23)`
As face- centred cubic unit cell contains 4 atoms, therefore,
Number of unit cells present =` (1.806 xx 10^(23))/4 = 4.515 xx 10^(22)`