Solid state practice · Mixed difficulty

A solid is made of two elements $X$ and $Z$. The atoms $Z$ are in ccp arrangement while the atom $X$ occupy all the tetrahedral sites. What is the formula of the compound?

The correct relationship between edge length (a) and radius of atom (r) for BCC unit cell is

For an ionic crystal of the general formula $AX$ and coordination number 6, the value of radius ratio will be

Assertion : No compound has both Schottky and Frenkel defects.

Reason : Both defects change the density of the solid.

Quartz is an example of :

The interionic distance for cesium chloride crystal will be

$\mathrm{CsBr}$ crystallises in a body centred cubic lattice. The unit cell length is 436.6 pm. Given that the atomic mass of $\mathrm{Cs} = 133$ and that of $\mathrm{Br} = 80$ amu and Avogadro number being $6.02 \times {10^{23}}\mathrm{mo}{\mathrm{l}^{ - 1}},$ the density of $\mathrm{CsBr}$ is :

Identify the crystal system having edge lengths a=b=c and inter-axial angles $\alpha = \beta = \gamma \ne {90^0}$

The unit cell with dimensions $\alpha = \beta = \gamma = 90^\circ ,a = b \ne c$ is

Potassium has a bcc structure with nearest neighbour distance $4.52\,\mathop \mathrm{A}\limits^ \circ .$ Its atomic weight is 39. Its density will be :

Which of the following compounds is likely to show both Frenkel and Schottky defects in its crystalline form?

For cubic coordination, the value of radius ratio is

A compound formed by elements $X$ and $Y$ crystallises in a cubic structure in which the $X\,atoms$ are at the corners of a cube and the $Y\,atoms$ are at the face centres. The formula of the compound is

If $\mathrm{Z}$ is the number of atoms in the unit cell that represents the closest packing sequence $- ABCABC - ,$ the number of tetrahedral voids in the unit cell is equal to :

Which species is paramagnetic?

The following is not a function of an impurity present in a crystal

A metal has bcc structure and the edge length of its unit cell is $3.04\mathop \mathrm{A}\limits^ \circ$. The volume of the unit cell in $\;\mathrm{c}{\mathrm{m}^3}$ will be

Assertion (A): Covalent crystal have the higher melting point.

Reason (R): Covalent bonds are stronger than ionic bonds.

Select the correct statements.
(A) Crystalline solids have long range order.
(B) Crystalline solids are isotropic
(C) Amorphous solids are sometimes called pseudo solids
(D) Amorphous solids soften over a range of temperatures.
(E) Amorphous solids have a definite heat of fusion
Choose the most appropriate answer from the options given below

The statement that, “It is possible to choose along the three co-ordinate axes unit distance $a,b,c$ not necessarily of the same length, such that the ratio of there intercepts of any plane in the crystal is given by in $ma:nb:pc$ where $m,n,p$ are either integral whole numbers including infinity or fraction of whole number” is known as :

In a face centred cubic cell, an atom at the face contributes to the unit cell

Which is an example of ferroelectric compound?

Gold crystallizes with a

The percentages of void space for simple cubic, body centered cubic and hexagonal close packed arrangement respectively are

Which among the following is an example of ferro magnetic compound

Right option for the ratio of number of octahedral voids and total octahedral and tetrahedral voids in face centred cubic unit cell is

Metallic crystalline solids :

Packing efficiency of fcc unit cell is

On doping $Ge$ metal with a little of $In$ or $Ga$. One gets what type semi-conductor

Assertion (A): In ${NaCl}$ crystal each ${Na}^{+}$ion is touching $6 \, {Cl}^{-}$ions but these ${Cl}^{-}$ions do not touch each other.

Reason (R): The radius ratio is greater than 0.414 required for exact fitting.