In a compound atoms of element Y form ccp
lattice and those of element X occupy 2/3rd of
tetrahedral voids. The formula of compound will
be
1.
2.
3.
4.
The edge length of fcc unit cell of NaCl is 508 pm.
If the radius of cation is 110 pm then radius of the anion is :
1. 244 pm
2. 144 pm
3. 288 pm
4. 398 pm
An element (Atomic mass = 50 g/mol) having
fcc structure has unit cell edge length 400 pm.
The density of element is
1. 5.188 g/cc
2. 10.376 g/cc
3. 2.56 g/cc
4. 1.2 g/cc
In a crystalline solid, anion B are arranged in
cubic close packing and cation A are equally
distributed between octahedral and tetrahedral
voids. If all the octahedral voids are occupied,
the formula for the solid is
1. AB
2. AB2
3. A2B
4. A2B3
In a face centred cubic lattice, atom a occupies
the corner positions and atom B occupies the
face centred positions. If one atom of B is
missing from one of the face centred points, the
formula of the compound is
1. A2B
2. AB2
3. AB
4. A2B5
A binary solid has a structure with B– ion constituting the lattice and A+ ion occupying 25% tetrahedral holes. The formula of solid is
1. AB
2. A2B
3. AB2
4. AB4
A solid has a bcc structure. If the distance of
closest approach between the two atoms 1.73Å.
The edge length of the cell is
1. 200 pm
2. pm
3. 142.2 pm
4. 400 pm
A metal crystallises as body centred cubic lattice
with the edge lenth of unit cell equal to 0.304
nm. If the molar mass of the metal is
50.3 g mol–1, its density is
1. 5.945 g cm–3
2. 2.9725 g cm–3
3. 8.9175 g cm–3
4. 4.458 g cm–3
Analysis shows that an oxide ore of nickel has
formula Ni0.98O1.00. The percentage of nickel as
Ni3+ ions is nearly
1. 2
2. 96
3. 4
4. 98
Perovskite is mineral contaning calcium, oxygen
and titanium, in which oxygen atoms are at the
face centres, calcium atoms are at the corners
and titanium atoms at the centre of the cube.
Oxidation number of titanium in the mineral is
1. +2
2. +3
3. +4
4. +3/4
In a crystal A atoms are present at all the corners
and face centres while B atoms at all the edge
centres and body centre of cubic unit cell. If the
atoms from one of the body diagonal are removed
then what will be the simplest composition of unit
cell?
1. A5B4
2. A15B12
3. A4B5
4. A2B3
The number of cation vacancies per mole in NaCl
crystal, if it is doped with 10–3 mole% GaCl3
(ionic salt), are
1. 6.02×1020
2. 6.02×1018
3. 1.204×1021
4. 1.204×1019
The packing efficiency of the two dimensional
square unit cell shown below is
1. 39.27%
2. 68%
3. 74%
4. 78.54%
In which operation(s) in the unit cell of sodium
chloride, formula of sodium chloride is
disturbed?
1. A body diagonal plane is placed
2. A tetrad axis is placed
3. A body diagonal line is placed
4. A rectangular plane is placed
Tetragonal crystal system does not has
1. Simple unit cell
2. Body centred unit cell
3. Face centred unit cell
4. All are present