Question

Match the types of packing given in column I with the items given in column II.

	Column I		Column II
(i)	Square close packing in two dimension	(p)	Triangular voids
(ii)	Hexagonal close packing in two dimensions	(q)	Pattern of spheres is repeated in every fourth layer
(iii)	Hexagonal close packing in three dimension	(r)	Coordination number=4
(iv)	Cubic close packing in three dimension	(s)	Pattern of spheres is repeated in alternate layers

• A. (i)- (p), (ii)- (r), (iii)- (q), (iv)- (s)
• B. (i)- (q), (ii)- (s), (iii)- (p), (iv)- (r)
• C. (i)- (r), (ii)- (p), (iii)- (s), (iv)- (q)
• D. (i)- (r), (ii)- (p), (iii)- (q), (iv)- (s)

Answer 1

Answer: (C)

(i)- (r), (ii)- (p), (iii)- (s), (iv)- (q)

Square close packing in 2D: In this kind of arrangement the AAA type of pattern of stacking is followed. The coordination number of each sphere in this arrangement will be $4$.

Hexagonal close packing in 2D has triangular voids as shown in the figure.

The pattern of arrangement in hcp and ccp in 3D is shown in the figure.