Distinguish clearly between salt like hydrides and covalent hydrides.

What do you understand by:
(i) electron deficient
(ii) electron-precise and
(iii) electron rich compounds of hydrogen?
Provide justification with suitable examples.

What characteristics do you expect from an electron-deficient hydride with respect to its structure and chemical reactivity ? 

Do you expect the carbon hydride of the type(C_nH_2n+2) to act as Lewis acid or base? 

What do you understand by the term ‘non-stoichiometic hydrides’? Do you expect this type of hydrides to be formed by alkali metals?

Saline hydrides are known to react with water violently producing fire. Can CO₂, a well-known fire extinguisher, be used in this case? Explain.

What do you expect the nature of hydrides if formed by elements of atomic numbers 15, 19, 23, 44 with dry dihydrogen? Compare their behaviour towards water. 

How saline hydrides can remove traces of water from organic compounds?

Can Phosphorus with outer electronic configuration 3s²3p³ form PH₅?
Or

P forms PH₃ but not PH₅. Comment.

100. Arrange the following:
CaH₂, BeH₂ and TiH₂ in order of increasing electric conductance.