Advertisements
Advertisements
Question
How will you distinguish between the following pair of terms?
Tetrahedral and octahedral voids
Advertisements
Solution
| Tetrahedral void | Octahedral void | |
| 1. | The tetrahedral void is the name given to the vacant space formed by the touching of four spheres, as shown in the figure. |
Octahedral voids are formed by the combination of voids of two triangular layers of atoms when one triangular layer is placed above another, as shown in the figure. |
| 2. | A tetrahedral void is surrounded by 4 atoms arranged at the corners of a tetrahedron. | An octahedral void is surrounded by 4 atoms arranged at the corners of an octahedron. |
| 3. | Found in close-packed structures like fcc and hcp. | Only present in close-packed structures. |
| 4. | Smaller in size compared to octahedral voids. | Larger in size than tetrahedral voids. |
| 5. | Number of tetrahedral voids = 2 × number of atoms in the lattice | Number of octahedral voids = equal to number of atoms in the lattice |
APPEARS IN
RELATED QUESTIONS
If the radius of the octahedral void is r and the radius of the atoms in close packing is R, derive the relation between r and R.
Total number of voids in 0.5 mole of a compound which forms hexagonal close packed structure is ____________.
If AgI crystallises in zinc blende structure with I– ions at lattice points. What fraction of tetrahedral voids is occupied by Ag+ ions?
In which of the following crystals alternate tetrahedral voids are occupied?
In the hexagonal close-packed structure of a metallic lattice, the number of nearest neighbours of a metallic atom is ____________.
If Germanium crystallises in the same way as diamond, then which of the following statement is not correct?
In which of the following arrangements octahedral voids are formed?
(i) hcp
(ii) bcc
(iii) simple cubic
(iv) fcc
The coordination number of Y will be in the XY types of crystal:
The number of tetrahedral voids per unit cell in NaCl crystal is:
(i) 4
(ii) 8
(iii) twice the number of octahedral voids.
(iv) four times the number of octahedral voids.
Show that in a cubic close packed structure, eight tetrahedral voids are present per unit cell.
