Assertion : Solids having more F-centre possess intense colour
Reason: Excess of `Na^(+)` in `NaCI` solid having F-centers makes it appear pink

Assertion : Solids having more F-centres possess intense colours. Reason : Excess of Na^(+) in NaCl solid having F-centres makes it appear to pink.

Solids containing F-centres are paramagnetic and coloured. Why?

Assertion (A) : Solids containing F centres are paramagnetic. Reason (R ) : Solids containing F centres conduct electricity and it is n -type semiconduction.

Assertion (A) : Solids containing F centres are paramagnetic. Reason (R ) : Solids containing F centres conduct electricity and it is n -type semiconduction.

Assertion (A) : Solids containing F centres are paramagnetic. Reason (R ) : Solids containing F centres conduct electricity and it is n -type semiconduction.

Assertion: Solid have definite volume and shape. Reason : In solid, the constituent particles are very close to each other and there is not much freedom of movement.