JEE Main 2014 · 11 Apr · Shift 1 · Chemistry Q32

ChemistrySingle correct+4 / -1Question 32 of 90

The appearance of colour in solid alkali metal halides is generally due to :

Schottky defect

Frenkel defect

Interstitial position

F-centres

Answer and worked solution

Official answer: D

Colour in alkali halide crystals (e.g. NaCl turning yellow when heated in Na vapour) comes from electrons trapped at anion vacancies: F-centres.

JEE Main 2014 · 11 Apr · Shift 1, Chemistry question 32