Consider the following statements I. NaCl and KCl show metal excess defect due to anionic vacancies II. F- centres are the anionic site occupied by unpaired electrons III. F-centres is derived from the germen word farbenzenter for colour centre . F-centres impart yellow colour to the NaCl crystals Which of the above statements is / are correct ?A. II, III and IVB. I, III and IVC. I, III and IIID. All of these

Consider the following statements I. NaCl and KCl show metal excess de

1.	Consider the following statements I. NaCl and KCl show metal excess defect due to anionic vacancies II. F- centres are the anionic site occupied by unpaired electrons III. F-centres is derived from the germen word farbenzenter for colour centre . F-centres impart yellow colour to the NaCl crystals Which of the above statements is / are correct ?A. II, III and IVB. I, III and IVC. I, III and IIID. All of these
Answer» Correct Answer - D Alkali metals like KCl and NaCl show metal deficiency defect. Due to loss of unpaired electron, Na changes to `Na^+ " and combine with " Cl^-` to form NaCl These unpaired electrons occupy anionic sites which is called F-centres that imparts yellow colour in the crystal.

Discussion

No Comment Found

Related InterviewSolutions

Iodine molecules are held in the crystals lattice by ……..A. London forcesB. dipole-dipole interractionsC. covalent bondsD. coulombic forces
Iodine molecules are held in the crystal lattice by:A. London forcesB. Dipole -dippole interactionsC. Covvalent bondsD. Coulombic forces
Which of the following compounds are not isomorphous? a. Copper sulphate and zine sulphate b. Zinc sulphate and manganeous sulphate c. Calcium carbonte and ferrous sulphate d. Zine sulphate and ferrous sulphate
How many unit cells are present in a cube-shaped crystal of NaCl of mass 1.00g?A. `2.57xx10^(21)` unit cellsB. `5.14xx10^(21)` unit cellsC. `1.28xx10^(21)` unit cellsD. `1.71xx10^(21)` unit cells
Which of the following statements is/are correct?A. Dislocation of ion from lattice site to intersitial site is called Frenkel defect.B. Missing of +ve and -ve ions from their respective postion producing a parir of holes is called Sschorttky defect.C. The presence of ions in the vacant intersitial sites along with lattice point is called interstital defect.D. Non-stoichiometric NaCl is yellow solid.
which of the following is not the characteristic of ionic solids?A. Very low value of electrical conductivity in the molten stateB. Brittle natureC. Very strong forces of interactionsD. Anisotropic nature
For which of the following cases, answer is `4`A. Coordination number of `Zn^(2+)` in `Z` inc blendeB. Number of body diagonal planes in a cubeC. Formula units in rock salt structureD. Formula units in `CsCl` structure
The existence of a substance in more the one solid modifications is known as//or .Any compound having more than two cystal structures is calledA. IsomorphismB. Polymorp hismC. NeomorphismD. Crystallomorphism
Ionic solids are characterised byA. Good conductivity in solid stateB. High vapour pressureC. Low melting pointD. Solubility in polar solvents
Aluminium metal has a density of `2.72 g cm^(-3)` and crystallizes in a cubic lattice with an edge of `404 pm`. Which of the following is correct?A. It forms bcc unit cellB. It forms fcc unit cellC. Its `CN = 8`D. Its `CN` is `6`

Discussion

No Comment Found

Related InterviewSolutions

Reply to Comment