Solid state practice · Medium

In the calcium fluoride structure, the coordination number of the cation and anion are respectively

The unit cell with crystallographic dimensions $a \ne b \ne c,\,\,\,\alpha = \gamma = {90^\mathrm{o}}$ and $\beta \ne {90^\mathrm{o}}$ is

p-type semiconductor is formed when germanium is doped with

What is common in HCP and FCC unit cell?

The number of atoms in 100 g of an fcc crystal with density $d = 10\mathrm{g/c}{\mathrm{m}^\mathrm{3}}$ and cell edge equal to 100 pm, is equal to

$\mathrm{A}, \mathrm{B}$ and $\mathrm{C}$ have the oxidation numbers of $+6,-2$ and $-1$ respectively, the possible molecular formula when these atoms combine will be:

Given below are two statements.
Statement I Frenkel defects are vacancy as well as interstitial defects.
Statement II Frenkel defects leads to colour in ionic solids due to presence of F - centres.
Choose the most appropriate answer from the options given below.

Close packing is maximum in the crystal lattice of :

The example of orthosilicate is :

The correct option for the number of body centred unit cells in all 14 types of Bravais lattice unit cells is:

An element has bcc structure having unit cells $12.08 \times {10^{23}}$. The number of atoms in these cells is :

Which among the following will show anisotropy?

If a crystal lattice of a compound, each corner of a cube is enjoyed by sodium, each edge of a cube has oxygen and centre of a cube is enjoyed by tungsten $(W)$, then give its formula

The fraction of the total volume occupied by the atoms present in bcc unit cell is

At zero kelvin, most of the ionic crystals possess.

The ratio of closed packed atoms to tetrahedral holes in cubic close packing is:

Which of the following statements is/are not true?

An example of a substance possessing giant covalent structure is

A substance AB crystallizes in cubic
closest packing (C.C.P.) with B occupying
half the tetrahedral voids. One litre of
the crystal is doped with 1 mole atoms of
C some of which replace the B atoms
and remaining occupy few interstitial
voids without affecting the dimensions of
cubic crystal lattice. If density of crystal
before doping is 4.8 gm/millilitre and
density after doping is 4.795 gm /ml then
calculate % of C added with replace B
atoms.
(Given : Atomic weight : A, B
and C : 40, 30, 15)

The ratio of number of atoms present in a simple cubic, body centered cubic and face centered cubic structure are, respectively.

Which kind of defect is shown by the given crystal?
${K^ + }C{l^ - }{K^ + }C{l^ - }{K^ + }C{l^ - }$
$C{l^ - }{ \Box }\,C{l^ - }{K^ + }{ \Box }\,{K^ + }$
${K^ + }C{l^ - }\,{ \Box }\,C{l^ - }{K^ + }C{l^ - }$
$C{l^ - }{K^ + }C{l^ - }{K^ + }{ \Box }{K^ + }$

Of the elements $\mathrm{Sr},\mathrm{Zr},\mathrm{Mo},\mathrm{Cd}\,\mathrm{ and}\;\mathrm{ Sb},$ all of which are in $V$ period, the paramagnetics are:

Liquid crystals are best used in:

Which of the following statements is not correct?

Assertion (A) Both Frenkel and Schottky defects are stoichiometric defects.

Reason (R) Both defects change the density of the crystalline solid.

Which of the following point defects are shown by Ag Br (s) crystals

i) Schottky defect ii) Frenkel defect

iii) Metal excess defect iv) Metal deficiency defect

Which type of solid crystals will conduct heat and electricity?

The correct statement regarding F-centre is

Which defect may be present in $NaCl$ crystal?

The edge of unit cell of fcc Xe crystal is 620 pm. The radius of Xe atom is