Question

sodium chloride face centered cubic lattice. if the length of cubic edge is 5.64A',then d220 is

Answer 1

Answer:

Explanation:

The expression for density is given below:

d=zM​/NA​a3 =z×58.5/6×1023×(5.623×10−8)3​=2.16 g cm−3

⟹z=4

So, the number of pairs of NaCl per unit cell is 4.

We know that 1 mole = NA​ no. of ions

∴ 4 NaCl ions =​4​/NA moles

Hence, the total no. of moles present per unit cell = NA​4​ moles