the number of unit cells in 58.5g of NaCl is approximately?

NaCl ( rock salt ) structure:
no. of edge center atoms = 12(edges) x 1/4 (each edges shared by 4 units)
=3
no. of body centred atoms = 1( center position) x 1 ( single atom present)
= 1
no of corner atoms = 8 (corners) x 1/8 (counribution of each atom to a unit cell )
= 1
no. of face centered atoms = 6 (no. of faces in a cube) x 1/2 (atoms contribution to single unit cell)
=3
there are 8 cubes ( units) in an ideal NaCl structure
coordination ration of NaCl=6:6
rank of NaCl = 4 ( no. of formula units )
no of NaCl molecule in aunit cell is 4
in 58.5 gm of NaCL no of mole is 1
in 1 mole of NaCl no of unit cell is Na/4