Question 1 :
If the anions (A) form hexagonal closest packing and cations (C) occupy only 2/3 octahedral voids in it, then the general formula of the compound is: 

Question 2 :
A metal crystallises into a lattice containing a sequence of layers as AB AB AB _______. What percentage of voids are left in the lattice?

Question 3 :
Sodium metal exists in bcc unit cell. The distance between nearest sodium atoms is $0.368\ nm$. The edge length of the unit cell is:

Question 5 :
Which one of the following schemes of ordering close-packed sheets of equal-sized spheres do not generate close-packed lattice?

Question 6 :
Match the column I with column II and mark the appropriate choice.<table class="wysiwyg-table"><tbody><tr><td></td><td>Column I<br>(Structure)</td><td></td><td>Column II<br>(Packing efficiency)</td></tr><tr><td>(A)</td><td>Simple cubic structure&nbsp;</td><td>(i)</td><td>68%</td></tr><tr><td>(B)</td><td>Face centered cubic structure</td><td>(ii)</td><td>74%</td></tr><tr><td>(C)</td><td>Body centered cubic structure</td><td>(iii)</td><td>52%</td></tr></tbody></table>

Question 8 :
Which one of the following schemes of ordering closed packed sheets of equal sized spheres do not generate&nbsp;close packed lattice?

Question 9 :
Starting from the rock salt structure, the crystal structure type generated by the removal of all ions of one type is:

Question 10 :
In $ccp$ arrangement the pattern of successive layers can be designed as:

Question 12 :
The packing efficiency in a body-centred cubic(bcc) structure is closest to:

Question 13 :
In a face centred cubic lattice, the number of nearest&#160;neighbours for a given lattice point is :