Advertisements
Advertisements
प्रश्न
Which of the following statement is not true about the hexagonal close packing?
पर्याय
The coordination number is 12.
It has 74% packing efficiency.
Tetrahedral voids of the second layer are covered by the spheres of the third layer.
In this arrangement spheres of the fourth layer are exactly aligned with those of the first layer.
Advertisements
उत्तर
In this arrangement spheres of the fourth layer are exactly aligned with those of the first layer.
Explanation:
Hexagonal close packing can be arranged by two layers
A and B one over another which can be diagrammatically represented as
Here, we can see easily that 1st layer and 4th layer are not exactly aligned. Thus, statement (iv) is not correct while other statements (i), (ii) and (iii) are true.
APPEARS IN
संबंधित प्रश्न
A compound forms hexagonal close-packed structure. What is the total number of voids in 0.5 mol of it? How many of these are tetrahedral voids?
How many lattice points are there in one unit cell of the following lattice?
Face-centred cubic
Aluminium crystallises in a cubic close-packed structure. Its metallic radius is 125 pm.
- What is the length of the side of the unit cell?
- How many unit cells are there in 1.00 cm3 of aluminium?
With the help of a labelled diagram show that there are four octahedral voids per unit cell in a cubic close packed structure.
How can you best describe the elongated octahedral structure of blue vitriol, CuSO4.5H2O?
The crystal system of a compound with unit cell dimensions a = 0.387, b = 0.387 and c = 0.504 nm and α = β = 90° and ϒ = 120° is
Total no. of voids in 0.5 mole of a compound forming hexagonal closed packed structure are:-
The packing efficiency of the two dimensional square unit cell shown below is:
A compound forms hexagonal close-packed structure. What is the total number of voids in 0.5 mol of it? How many of these are tetrahedral voids?
Co-ordination number of sodium ion Na+ in Nacl is:-
Which of the following is frenkal effect.
The number of tetrahedral and octahedral voids in a CCP array of 100 atoms are respectively:
The right option for the number of tetrahedral and octahedral voids in hexagonal primitive unit cell is ______.
The empirical formula for a compound with a cubic close packed arrangement of anions and with cations occupying all the octahedral sites in AxB. The value of x is ______. (Integer answer)
The density of a pure substance 'X' whose atoms pack in cubic close pack arrangement is 1 g/cc. If all tetrahedral voids are occupied by 'Y' atoms. The value of '3a' is ______ g/cc, if the density of resulting solid is 'a' g/cc.
[Given: Atomic mass (X) = 30 g/mol, (Y) = 20 g/mol]
What fraction of one edge centred octahedral void lies in one unit cell of FCC?
