Packing refers to the arrangement of constituent units in such a way that the forces of attraction among the constituent particles is maximum and the constituents occupy the maximum available space. In two -dimensions ,there are square close packing and hexagonal close packing .In three- dimensions ,however, there are hexagonal close packing, cubic close packing and body-centered cubic packing. (i) hcp:AB AB AB AB ..... arrangement ""coordination no. = 12 "" % occupied space = 74 (ii) ccp:ABC ABC.... arrangement "" coordination no. = 12 ""% occupied space = 74 bcc:68% space is occupied ""coordination no.= 8 The A certain oxide of metal M crystallises in suchway that O^(2-) ions occupy hcp arrangement following AB AB....pattern. The metals ions ,however ,occupy (2)/(3)rd of the octahedral voids. The formula of the compound is:

Packing refers to the arrangement of constituent units in such a way t

1.	Packing refers to the arrangement of constituent units in such a way that the forces of attraction among the constituent particles is maximum and the constituents occupy the maximum available space. In two -dimensions ,there are square close packing and hexagonal close packing .In three- dimensions ,however, there are hexagonal close packing, cubic close packing and body-centered cubic packing. (i) hcp:AB AB AB AB ..... arrangement ""coordination no. = 12 "" % occupied space = 74 (ii) ccp:ABC ABC.... arrangement "" coordination no. = 12 ""% occupied space = 74 bcc:68% space is occupied ""coordination no.= 8 The A certain oxide of metal M crystallises in suchway that O^(2-) ions occupy hcp arrangement following AB AB....pattern. The metals ions ,however ,occupy (2)/(3)rd of the octahedral voids. The formula of the compound is:
Answer» `M_(2)O_(3)` `M_(3)O` `M_(8//3)O_(3)` `MO_(2)` ANSWER :A