Question

How will you distinguish between the Hexagonal close packing and cubic close packing?

Answer 1

Difference between hexagonal close packing and cubic close packing:

Hexagonal close packing	Cubic close packing
(1) By this type of packing tetrahedral voids are covered by spheres.	(1) By this type of packing octahedral voids are covered by spheres.
(2) Here the spheres in every third or alternate are vertically aligned i.e., the third layer is directly above the first, the fourth above the second layer and so on.	(2) Here the spheres in every fourth layer will be vertically aligned i.e., the fourth layer is directly above the first and the fifth layer is above the second layer.
(3) This type of pattern is called AB-AB type.	(3) This type of pattern is called ABC-ABC type.
(4) It is found in Mg and Zn	(4) It is found in Cu, Ag, Au etc.
(5)	(5)