The appearance of colour in solide state of alkali metal halides is generally due to `:`A. Frenkel defectB. Interstitial positionsC. `F-`centresD. Schottky defect

The appearance of colour in solide state of alkali metal halides is ge

1.	The appearance of colour in solide state of alkali metal halides is generally due to `:`A. Frenkel defectB. Interstitial positionsC. `F-`centresD. Schottky defect
Answer» Correct Answer - c Presence of excess `Na ` in `NaCl` makes it yellow, presence of excess `Li` in `LiCl` makes it pink, presence of excess `K` in `KCl` makes it violet. Greater the no. of `F-` centres, greater is intensity of colour.

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The appearance of colour in solide state of alkali metal halides is generally due to `:`A. Frenkel defectB. Interstitial positionsC. `F-`centresD. Schottky defect

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