The Lewis bases are those which can donate electron pair to an acceptor. These electrons can be a pair of electron that is a lone pair, a negative charge or electrons in a $\pi$ -bond.

In $H-C\equiv C-H$ , the presence of $\pi$ -bond make it a Lewis base.
In $H^{-}$ , the presence of negative charge makes it a Lewis base.
In $NH_3$ , the presence of lone pair on nitrogen makes it a Lewis base.
In $CH_3CH_2CH_3$ , there is no lone pair, no $\pi$ -bond, no negative charge so it is not a Lewis base.

Hence, $H-C\equiv C-H$ , $H^{-}$ , and $NH_3$ are Lewis bases.

8 0

3 years ago

Which element has the smallest atomic radius

grandymaker [24]

I believe it's helium at 0.49 A

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3 years ago

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