Explain with suitable example the following
i) electron - deficient
ii) electron - precise and
iii) electron - rich hydrides

i) electron - deficient hydrides: The molecular hydrides in which the available valency electrons of the central atom are less than required for bond formation are called electron
- deficient hydrides.
Eg: B₂H₆
ii) electron - precise hydrides: The molecular hydrides in which all the valency electron of the central atom are involved in the bond formation are called electron precise hydrides.
Eg: CH₄
iii) electron - rich hydrides: The molecular hydrides in which the available valency electrons of the central atom are more than required for bond formation are called electron - rich hydrides.
Eg: $\stackrel{..}{\mathrm{N}}{\mathrm{H}}_3$