Q59 / 180 · AIIMS 2008 · Chemistry

The flame colours of metal ions are due to

A
Frenkel defect
B
Schottky defect
C
metal deficiency defect
Correct answer
D
metal excess defect.

Solution

This defect arises when a compound has excess metal ion. If a negative ion is absent from its lattice site leaving a hole occupied by electron. The holes occupied by electrons are called F- centres. Greater the number of F-centres greater is the intensity of colour.

Hence, the correct answer is option: 'D'.

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