AP EAMCET20226 Jul 2022Morning ShiftChemistrySolid StateActual
F-centres are formed in NaCl crystal if it is heated with Na vapour. The above is due to
Options
- ASchottky defect
- BDislocation defect
- CMetal excess defect
- DMetal deficiency defect
Correct answer
C. Metal excess defect
Step-by-step solution
The crystal lattice has vacant anion sites, which are occupied by electrons. Anion sites occupied by electrons are called F -centres ( F is abbreviated from Farbe, the German word for colour. These F-centres are associated with the colour of the compound and the more F-centres present, the greater the intensity of the coloration. F-centre containing solids are paramagnetic, photoconductors.