Question

Name the non stoichiometric point defect responsible for colour in alkali metal halides

Answer 1

metal excess defect which is responsible for occurrence of f -centre

Answer 2

Non-stoichiometric defect responsible for color in alkali metal halide is metal excess (anion -vacancy) defect.

Explanation:

• Metal excess defect is accountable for mainly colour in 'alkyl halides'.

• For example, When crystals of NaCl are heated in an atmosphere of Na vapor, the Na atoms are accumulated on the surface of the crystals.

• And $Cl^-$ ions 'diffuse' to the 'surface' of the crystals to 'combine' with Na to form NaCl.

• This occurs by 'loss of electrons' by Na atoms to create$Na^+.$
• These liberate electrons distribute into the crystals and utilise anionic sites and imparts colour to crystal.

Learn more about alkali metal

A hydride of 2nd period alkali metal (A) on reaction with compound of Boron (B) to give a

reducing agent (C). identify A , B and C.​

https://brainly.in/question/9486954

Someone please give the difference of alkali metals and halogens

https://brainly.in/question/5637439