Assertion : Solids having more F-centre possess intense colour Reason: Excess of `Na^(+)` in `NaCI` solid having F-centers makes it appear pink
Text Solution
Verified by Experts
The correct Answer is:
a
Excess of `Na^(+)` in `NaCl` solid at `F-` centres develops yellow colour.
Topper's Solved these Questions
SOLID STATE
P BAHADUR|Exercise Exercise 9|1 Videos
MOCK TEST PAPER
P BAHADUR|Exercise Exercise|92 Videos
SURFACE CHEMISTRY
P BAHADUR|Exercise Exercise 5|1 Videos
Similar Questions
Explore conceptually related problems
Assertion (A) : Solids containing F centres are paramagnetic. Reason (R ) : Solids containing F centres conduct electricity and it is n -type semiconduction.
Assertion : Non-polar molecular solids have higher melting points than polar molecular solids. Reason : Non-polar molecular solids have weak London or dispersion forces between their molecules while polar molecules have strong dipole-dipole forces between their molecules.
Assertion (A) : Both CO_2 snd SiO_2 have same strucitrue . Reason (R) : CO_2 is a gas , whereas SiO_2 is a solide .
Assertion : The crystalline solids have a sharp melting point. Reason: All the bonds between the atoms or molecules fo a crystalline solids are equally strong, that they get broken at the same temperature.
Read assertion and reason carefully to mark the correct option. Assertion: Heavy nuclides tend to have more number of neutrons than protons. Reason: In heavy nuclei, as there is coulomb repulsion between protons, so excess of neutrons are preferable.
Assertion : At resonance, LCR series circuit have a minimum current. Reason : At resonance, in LCR series circuit, the current and e.m.f. are not in phase with each other.