Question

2.925g of cube shaped crystal of NaCl contains the number of unit cells_and_number of unit cells along each edge of that crystal respectively​

Answer 1

Explanation:

Molar mass of NaCl=58.5

1g of NaCl contains =

58.5

1

moles of NaCl

1g of NaCl contains

58.5

1

×6.022×10

23

molecule of NaCl in cube-shaped ideal crystal of NaCl (Rock salt type)

4 molecule of NaCl are present as Cl

−

present occupy the FCC lattice=4 ions of Ce

−

Na

+

occupy the octanedral site =4 ions of Na

+

1 unit cell contain 4 molecules of NaCl

1 molecule contain

4

1

unit cell

58.5

1

×6.022×10

23

molecule contains=

58.5

1

×

4

6.022×10

23

unit cell

Thus

1g of NaCl contain=2.57×10

21

unit cell.

Answer 2

Answer:

7.25*10^21 unit cells

Explanation:

given mass,m=2.925gm

molecular mass of NaCl=23+35.5=58.5

58.5 gm NaCl contains 6.023*10^23 unit molecules

then 2.925 gm of NaCl contains

= 2.925*6.023*10^23

58.4*4

(each NaCl molecule contains 4 NaCl unit cell)

= 17.67*10^23

234

=0.0752*10^23

=7.52*10^21 unit cells