Question

Why $BF_{3}$ forms adduct with ammonia? Explain with reaction.

Answer 1

On reaction of Boron trifluoride $BF_{ 3 }$ with the Ammonia $NH_{ 3 }$,the lone electron pair from  $NH_{ 3 }$ is donated to boron.

There is adduct which is formed because of the covalent bond between Boron trifluoride $BF_{ 3 }$with the Ammonia $NH_{ 3 }$. Since it is due to the gaining tendency of electron in Boron trifluoride $BF_{ 3 }$ as it is lewis acid and the donating tendency of electron in the Ammonia $NH_{ 3 }$ as it is Lewis base.

Answer 2

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MATE IT IS BECAUSE AMMONIA IS A LEWIS BASE.
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