Lewis Acids and Bases

[Victoria Dao 3G]

Why B(OH)3 is considered a lewis acid (sapling #6 in chemical bond section)?

[Tessa House 3A]

Boron only needs to have 6 valence electrons, so B(OH)3 has boron with three single bonds to oxygen (which are each bonded to a hydrogen). This means that there is room for a lewis base to come in and donate two electrons to boron, giving it 8 valence electrons and another bond. Because B(OH)3 accepts electrons from a lewis base that donates a lone pair, it is considered a lewis acid. I hope this helps!

[605291562]

Hi! I agree with what was said above, I think it is easiest to tell if you draw out the molecule because then you can clearly see that it will accept electrons.

[Joshua Chung 2D]

Writing out the lewis structure would help here. In this compound, boron has only three bonds and no lone pairs, so can easily accept electrons from a lewis acid.