Question

which type of defect is shown by kbr?

Answer 1

Metal excess defect due to anionic vacancies: Alkali halides like NaCl and KCl show this type of defect. When crystals of KCl are heated in an atmosphere of potassium vapour, the Potassium atoms are deposited on the surface of the crystal. The Cl– ions diffuse to the surface of the crystal and combine with K atoms to give KCl. This happens by loss of electron by sodium atoms to form K+ ions. The released electrons diffuse into the crystal and occupy anionic sites. As a result the crystal now has an excess of Potassium. The anionic sites occupied by unpaired electrons are called F-centres, these impart a violet colour to the KCl crystal also any alkylhalide shows schottky defect