Oxygen atoms forms fcc unit cell with 'A' atoms occupying all tetrahedral voids and 'B' atoms occupying all octahedral voids. If atoms are removed from two of the body diagonals then  the formula of resultant compound formed is: 

A solid has a structure in which W atoms are located at the corners of a cubic lattice. Oxygen atom at the centre of the edges and Na atom at centre of the cube. The formula of the compound is 

An element (atomic mass = 100 g mole) having a BCC structure has a unit cell edge of 400 pm. The density of the element is :

The radius of Ag⁺ ion is 126 pm and that I^- ion is 216 pm. The coordination number of Ag⁺ ion is

Schottky defect occurs mainly in electrovalent compounds where :

Analysis shows that an oxide ore of  nickel has formula  Ni_0.98O_1.00. The percentage of nickel as Ni³⁺ ions is nearly

The appearance of color in solid alkali metal halides is generally due to:-

CsBr has a (bcc) arrangement and its unit cell edge length is 400 pm. Calculate the interionic distance in CsBr.

MgO and NaCl has similar structure. In MgO , magnesium is surrounded by how many oxygen atoms :

Ice crystallizes in a hexagonal lattice having the volume of the unit cell as $132\times {10}^{-24} c{m}^3$. If the density is 0.92 g/cm³ at a given temperature, then number of  $H_{2}O$ molecules per unit cell is : 

AB crystallizers in a body-centred cubic lattice with edge length a equal to 387 pm. The distance between two oppositely charged ions in the lattice is : 

In a face centred cubic lattice, atom A occupies the corner positions and atom B occupies the face
centre positions. If one atom of B is missing from one of the face centred points, the formula of the compound is

1.AB₂

2.A₂B₃

3.A₂B₅

4.A₂B

Percentage of free space in cubic close packed structure and in body centered packed structure are respectively:

Packing fraction of simple cubic crystal lattice is 

In which of the following crystals alternate tetrahedral voids are occupied : 

In a metal oxide, the oxide ions are arranged in hexagonal close packing and metal ions occupy two third of the octahedral voids. The formula of the oxide is : 

The edge length of fcc unit cell of NaCl is 508 pm. If the radius of cation is 110 pm, then the radius of the anion is : 

A crystal is made of particle X, Y & Z. X forms FCC packing, Y occupies all octahedral

voids of X and Zoccupies all tetrahedral voids of X, if all the particles along one body

diagonal is removed then the formula of the crystal would be –

In a hypothetical solid C atoms are found to form cubical close packed lattice. Aatoms occupy all tetrahedral vioids& B atoms occupy all octahedral voids. A and B atoms are of appropriate size, so that there is no distortion in CCP lattice of C atoms. Now if a plane as shown in the following figure is cut.

Then the cross section of this plane will look like.

In hexagonal close packing of sphere in three dimensions.

Diamond has face-centred cubic lattice. There are two atoms at (0,0,0) and $\left(\frac{{\displaystyle 1}}{{\displaystyle 4}},\frac{{\displaystyle 1}}{{\displaystyle 4}},\frac{{\displaystyle 1}}{{\displaystyle 4}}\right)$coordinates.The ratio of the carbon-carbon bond distance to the edge of the unit cell is

Spinel is an important class of oxides consisting of two types of metal ions with the oxide ions arranged inCCP pattern. The normal spinel has 1/ 8 of the tetrahedral holes occupied by one type of metal ion and 1/2 of the octahedral holes occupied by another type of metal ion. Such a spinel is formed by Zn²+, A1³* and 0^2-with Zn²+ in the tetrahedral holes. If CCP arrangement of oxide ions remains undistorted in the presence of all the cations, formula of spinel and fraction of the packing fraction of crystal are respectively :

What is the maximum number of layers of atoms in close packed planes that will lie within two imaginaryparallel planes having a distance between them of 13$\sqrt{\frac{2}{3}}$ R (where R is the radius of atom) in the coppercrystal (FCC) ? Consider the atoms to be within the parallel planes if their centresare on or within the two parallel planes.

Analysis show that nickel oxide consist of nickel ion with 96% ions having d⁸ configuration and 4% having d⁷ configuration. Which amongst the following best represents the formula of the oxide.

PCl₅ molecule has

Which of the following statements is correct about the conduction of electricity in pure crystal of silicon atroom temperature?

Calculate the Miller indices of crystal planes which cut through the crystal axes at (i) (2a, 3b, c), (ii) (∞, 2b, c )

Caculate the distance between 111 planes in a crystal of Ca. Repeat the calculation for the 222 planes. (a = 0.556nm)

A metallic element crystallizes into a lattice containing a sequence of layers of ABABAB ............ Any packing of spheres leaves out voids in the lattice. The percentage by volume of empty space of this is

Silver metal crystallises in a cubic closest – packed arrangement with the edge of the unit cell having a length a = 407 pm. What is the radius of silver atom.