A metal has density of 4500 kg/m 3 with an fcc crystal structure and edge length is 400 pm. The number of unit cells present in 1 kg of the metal is n × 10 24 . Value of n is . (upto two decimal place)
The radius of Ag + ion is 126 pm while that of I – ion is 216 pm. The co-ordination number of Ag + in Agl is:
SrO is doped with 10 -4 mol % of Sr +4 The concentration of created cation vacancies is N A × 10 x per mol. Value of x is .
The following diagram shows the arrangement of lattice points with a = b = c and α = β = γ = 90 ° . Choose the correct options.
The % vacant space in bcc lattice cell is ———-
A metal crystallizes into two cubic phases, face-centred cubic (fcc) and body-centred cubic (bcc) whose unit cell lengths are 3.6 and 3.0 Å , respectively. Calculate the ratio of densities of fcc and bcc.
A metal crystallizes in f.c.c.[face centered cubic] Then, the ratio of number of its first nearest neighbours to the second nearest neighbours is ……………..
A crystal has KCl type structure. In this crystal, shortest distance between a cation and anion is 200 pm. The volume of the unit cell is a × 10 -22 cm 3 . Value of a is
Analysis show that nickel oxide consists of nickel ion with 96% ions having d 8 configuration and 4% having d 7 configuration. Which amongst the following best represents the formula of the oxide?
In an anti fluorite structure, cations occupy
In a body-centred cubic unit cell of caesium
Correct statement(s) related to spinel structure is/are:
If ‘a’ is the edge length of a unit cell, then correct option(s) is/are:
Which of the following statements are correct?
identify the correct statement(s).
In zinc blende (ZnS) structure, the co-ordination number of Zn 2+ ion is:
The radius of Ag + ion is 126 pm while that of I – ion is 216 pm. The co-ordination number of Ag in Agl is relatively higher, then its value is
The co-ordination number of Al in crystalline state of AICl 3 is
Crystal can be classified into .. basic crystal habits.
Experimentally it was found that a metal oxide has formula M 0 .98 O . Metal M , is present as M 2 + and M 3 + in its oxide. Fraction of the metal which exists as M 3 + would be :
CsCl crystallises in body centred cubic lattice. If ‘a’ is its edge length then which of the following expressions is correct ?
The correct statement(s) for cubic close packed (ccp) three dimensional structure is (are):
Consider an ionic solid MX with NaCl structure. Construct a new structure (Z) whose unit cell is constructed from the unit cell of MX following the sequential instructions given below. Neglect the charge balance. (i) Remove all the anions (X) except the central one ii) Replace all the face centered cations (M) by anions (X) (ii) Remove all the corner cations (M) (iv) Replace the central anion (X) with cation (M) The value of number of anions number of cations in Z is …….
Which of the following statement is true for ionic solids?
Orthorhombic crystal has the following unit cell parameters
Which one is called pseudo solid ?
A spinel is an important class of oxides consisting of two types of metal ions with the oxide ions arranged in ccp layers. The normal spinel has one-eighth of the tetrahedral holes occupied by one type of metal ion and one-half of the octahedral holes occupied by another type of metal ion. Such a spinel is formed by Mg 2 + , Al 3 + and O 2 − . The neutrality of the crystal is being maintained. Antispinels will differ in arrangements among cations, but anions will be still fcc .
In seven possible crystal system how many crystal system have more than one Bravais lattice
Calculate the value of Z 10 . Where Z = Co-ordination number of 2D – square close packing + Co-ordination number of 2D-hpc + Co-ordination number of 3D-square close packing + Co-ordination number of 3D, ABCABC .. . . . Packing + Co-ordination number of 3D, ABAB . . . . hcp Packing
Select the correct (s)
Select the correct statement (s)
Triclinic crystal has the following unit cell parameters :
Given : Radius of A 2+ = 100 pm; Radius of C + = 240 pm; Radius of B 2- = 300 pm; Radius of D – = 480 pm. Which is / are correct statement?
First three nearest neighbour distance for body centred cubic lattice are respective.
In Bragg’s X-ray diffraction studies, 100 pm X-ray has second-order diffraction at glancing angle of 30 0 . The interplanar spacing in the crystal in pm is
Which of the following statements are correct?
Crystal can be classified into. basic crystal habits.
Which of the following compounds is likely to show both Frenkel and Schottky defects in its crystalline form?
Which of the following compounds represent a normal 2:3 spinel structure ?
If a solid A + B − having ZnS (zinc blends) structure is heated so that the ions along two of the axis passing through the face centre particles are lost and bivalent ion (Z) enters here to maintain the electrical neutrality, so that the new formula unit becomes A x B y Z c report the value of x + y + c .
Which of the following crystal systems contains a group of equidistance lattice points as shown by the figure?
Among the following solids the number of ionic solid (a) Tetra phosphorus deca-oxide (P 4 O 10 ) (b) Graphite (c) Brass (d) Ammonium phosphate (NH 4 ) 3 PO 4 (e) SiC (f) Rb (g) I 2 (h) LiBr (i) P 4 (j) Si (k) Plastic
A solid has a cubic structure in which X atoms are located at the corners of the cube, Y atoms are at the cube centres, and O atoms are at the edge centers. What is the formula of the compound is XYO a ?. The value of a is
In cubic ZnS,the radii of the Znand S atoms are 0.83 A o and 1.74 A o respectively. What is the edge length of the unit cell of ZnS?
An element with atomic mass 48 g / mol forms an fcc lattice. The edge length of lattice is 400 pm and observed density is 4.2 g/cm 3 . Fraction of occupied space is .
The cubic unit cell structure of a compound containing cation M and anion X is shown below. When compared to the anion, the cation has smaller ionic radius. Choose the correct statement(s).
Select the incorrect statement about ABAB …… type two dimensional arrangement (two dimensional hexagonal unit cell)
Match the column Column I Column II (P) a = b ≠ c , α = β = 90 ∘ , γ = 120 ∘ (1) Tetragonal (Q) a ≠ b ≠ c , α = β = γ = 90 ∘ (2) Monoclinic (R) a ≠ b ≠ c , α = β = 90 ∘ , γ ≠ 90 ∘ (3) Orthorhombic (S) a = b ≠ c , α = β = γ = 90 ∘ (4) Hexagonal
In an fcc unit cell, atoms are numbered as shown below. The atoms not touching each other are (Atom numbered 3 is face centre of front face)
Which of the following cubic system does not exist
Caesium atoms are the largest naturally occurring atoms. The radius of Cs atom is 2.6 A o . The number of moles of Cs atoms to be laid side by side to give a row of Cs atoms 2.50 cm x × 10 -17 . Find the value of x.
In a face centred cubic lattice, atom A occupies the corner positions and atom B occupies face centre positions, if one atom of B is missing from one of the face centred points, the formula of the compounds is A 2 B x the value of x is :
A compound M p X q has cubic close packing (ccp) arrangement of X and bcc packing of M. The sum of p+q will be
In a CPS (Closed Packed Structure) of mixed oxides, it is found that lattice has O 2- (oxide ions) and one-half of octahedral voids are occupied by trivalent cations (A 3+ ) and one-eight of tetrahedral voids are occupied by divalent cations (B 2+ ). Based on derived formula of the mixed oxide the correct statements will be
An element crystallises as face centred cubic lattice with density as 5.20 g / cm 3 and edge length of the side of unit cell as 300 pm. The mass of the element which contains 3.0×10 24 cannot be equal to
The NaCl lattice has the cubic unit cell as shown.The correct statements are .
Which are amorphous solids ?
Which of the following statements is/are correct?
In a CsCl type crystal:
The correct statement(s) regarding defects in solid is (are):
Ferrous oxide (FeO) crystal has a cubic structure and each edge of the unit cell is 5.0 A o . Taking density of the oxide as 4.0 g cm -3 . The number of FeO formula units present in each unit cell is:
The number of hexagonal faces that are present in a truncated octahedron is
The number of formula units of NaCl in an unit cell of its crystal is
In hexagonal systems of crystals, a frequently encountered arrangement of atoms is described as a hexagonal prism. Here, the top and bottom of the cell are regular hexagons and three atoms are sandwiched in between them. A space-filling model of this structure, called hexagonal close-packed (hcp), is constituted of a sphere on a flat surface surrounded in the same plane by six identical spheres as closely as possible. Three spheres are then placed over the first layer so that they touch each other and represent the second layer. Each one of these three spheres touches three spheres of the bottom layer. Finally, the second layer is covered with a third layer that is identical to the bottom layer in relative position. Assume radius of every sphere to be ‘r’.
The arrangement of X – ions around A + ion in solid AX is given in the figure (not drawn to scale). If the radius of X – is 250 pm, the radius of A + is :
A compound M p X q has cubic close packing (ccp) arrangement of X. Its unit cell structure shown below. The empirical formula of the compound is:
Which type of ‘defect’ has the presence of cations in the interstital sites?
A crystalline solid of a pure substance has a face centred cubic structure with a cell edge of 400 pm. If the density of the substance in the crystal is 8 g cm -3 , then the number of atoms present in 256 g of the crystal is N × 10 24 . The value of N is:
A metal crystallises in a face centred cubic structure. If the edge length of its unit cell is ‘a’, the closest approach between two atoms in metallic crystal will be:
Element B’ forms ccp structure and ‘A’ occupies half of the octahedral voids, while oxygen atoms occupy all the tetrahedral voids. The structure of bimetallic oxide is:
Solids which do not show the same physical properties in different directions are called:
Graphite is an example of
Crystals which are good conductor of electricity and heat are
Amorphous solids are:
The bond length and bond angles in molecules in the solid state are calculated by:
In a hexagonal crystal :
Density of a unit cell is represented as ρ = Effective no. of atom ( s ) × Atomic mass / formula mass Volume of a unit cell = Z ⋅ M . N A ⋅ a 3 where, mass of unit cell = mass of effective no. of atom(s) or ion(s) M = At. mass/formula mass N A = Avogadro’s no. ⇒ 6 .023 × 10 23 α = edge length of unit cel
Packing fraction of an identical solid sphere is 74% in :
In seven possible crystal system how many crystal system have more than one Bravais lattice
In solid X atoms goes to corner of the cube and two alternate face centre. Calculate effective number of atom of X in unit cell ?
The structure of MgO is similar to rock salt structure. What is the co-ordination number of Mg?
What is the co-ordination number of sodium in Na 2 O ?
How many effective no. of atoms present in bcc unit cell?
Select the correct statement(s) for the rock-salt structure (NaCl)
Ionic solid Na + A – crystallise in rock salt type structure. 2.592 gm of ionic solid salt NaA dissolved in water to make 2 litre solution. The pH of this solution is 8. If distance between cation and anion is 300 pm, calculate density of ionic solid (in gm/cm 3 ) . (Given : pK w = 13 , pK a ( HA ) = 5 , N A = 6 × 10 23 )
Select the correct statement(s)
Select the correct statement(s):
In fcc structure octahedral voids are present at
The ionic radii of A + and B − are 1 .7 Å and 1 .8 Å respectively. Find the co-ordination number of A +
Which is / are correct statement about zinc blende structure?
When heated above 916°C, iron changes its bcc crystalline form to fcc without the change in the radius of atom. The ratio density of the crystal before heating and after heating is
Sodium (Na = 23) crystallizes in bcc arrangement with the interfacial separation between the atom at the edge 53.6 pm. The density of sodium crystal is:
Given : The unit cell structure of compound is shown below. The formula of compound is:
First three nearest neighbouring distance for primitive cubic lattice are respectively (edge length of unit cell = a),which combinations are incorrect
lonic lattice has two major points defects, (1) Schottky (2) Frenkel defects Schottky defects occurs due to the cation-anion pair’s missing from the lattice sites. Frenkel defects occurs when an ion leaves its lattice site and fits into an interstitial space. The neutrality of the crystal is being maintained and we considered all losses from interstitial positions
The number of formula units of NaCl in an unit cell of its crystal is
Identify the correct statement(s).
If ‘a’ is the edge length of a unit cell, then correct option(s) is/are:
The number of hexagonal faces that are present in a truncated octahedron is
Which are amorphous solids?
The co-ordination number of Al in crystalline state of AlCl 3 is
Which of the following statements are correct?
