Which of the following is not true about the voids formed in 3 dimensional hexagonal close packed structure ?

(a) A tetrehedral void is formed when a sphere of the second layer is present above triangular void in the first layer

(b) All the triangular voids are not covered by the spheres of the second layer

(c) Tetrahedral voids are formed when the triangular voids in the second layer lie above the triangular voids in the first layer and the triangulare shapes of these voids do not overlap

(d) Octahedral voids are formed when the triagular voids in th second layer exactly overlap with similar voids in the first layer

Q.

Which of the following statement is not true about the hexagonal close packing ?

(a) The coordination number is 12

(b) It has 74% packing efficiency

(c) Tetrahedral voids of the second layer are covered by the spheres of the third layer

(d) In this arrangement spheres of the fourth layer are exactly aligned with those of the first layer

Q. In octahedral holes (voids)

Q. A compound forms hexagonal close-packed structure. What is the total number of voids in 0.5 many of these are tetrahedral voids?

Q. A compound forms hexagonal close-packed structure. What is the total number of voids in $0.5mol$ of it.How many of these are tetrahedral voids?

Q.

Which of the following is not true about the ionic solids ?

(a) Bigger ions form the close packed structure

(b) Smaller ions occupy either the tetrahedral or the octahedral voids depending upon their size

(c) Occupation of all the voids is not necessary

(d) The fraction of octahedral or tetrahedral voids occupied depends upon the radii of the ions occupying the voids