Advertisements
Advertisements
Question
Gold (atomic radius = 0.144 nm) crystallises in a face-centred unit cell. What is the length of a side of the cell?
Advertisements
Solution
For a face-centred unit cell:
`a = 2 sqrt 2 r`
It is given that the atomic radius, r = 0.144 nm
So, `a = 2 sqrt 2 xx 0.144` nm
= 2 × 1.414 × 0.144 nm ...`(∴ sqrt2 = 0.414)`
= 0.407 nm
Hence, length of a side of the cell = 0.407 nm
RELATED QUESTIONS
Which is true for F-centers?
Which crystal system has axial angles equal to 90°?
Coordination numbers of Zn2+ and S2– in the crystal structure of wurtzite are ____________.
In face-centered cubic lattice, a unit cell is shared equally by how many unit cells?
The total number of tetrahedral voids in the face-centered unit cell is ______.
In zinc blend structure:
A unit cell of BaCl2 (fluorite structure) is made up of ____________.
The distance between Na– and Cl– ions in NaCl with a density 2.165 g cm–3 is __________.
Assertion: Total number of octahedral voids present in unit cell of cubic close packing including the one that is present at the body centre, is four.
Reason: Besides the body centre there is one octahedral void present at the centre of each of the six faces of the unit cell and each of which is shared between two adjacent unit cells.
A crystal has the lattice parameters a ≠ b ≠ c and α = β = γ = 90°. The crystal system is
Na and Mg crystallise in Bee and Fcc type crystals respectively. "The no. of atoms in the unit cells of their respective crystals is:
Sodium crystallises in a body-centred cubic unit cell. (bcc) with edge length 4.29 A. what is the radius of the sodium atom? What is the length of the body diagonal of the unit cell?
The correct option for the number of body-centered unit cells in all 14 types of Bravais lattice unit cells is ______.
The correct option for the number of body-centered unit cells in all 14 types of Bravais lattice unit cells is ______
A certain element crystallises in a bcc lattice of unit cell edge length 27 A°. If the same element under the same conditions crystallises in the fcc lattice, the edge length of the unit cell in A° will be ______. (Round off to the Nearest Integer).
[Assume each lattice point has a single atom]
Gold crystallizes in a face-centered cubic lattice. If the length of the edge of the unit cell is 407 pm. The density of gold assuming it to be spherical is ______ g/cm3. Atomic mass of gold = 197 amu.
Which primitive unit cell has unequal edge lengths (a ≠ b ≠ c) and all axial angles different from 90°?
